Move V8 CHANGES to Changes chapter.

3 files changed, 3540 insertions, 3305 deletions

diff --git a/CHANGES.md b/CHANGES.md
index a7d02e75ff..9a260a9615 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,5 @@
-Changes from 8.9 to 8.10
-========================
+Unreleased changes
+==================
 
 OCaml and dependencies
 
@@ -262,3298 +262,3 @@ Diffs
 
 - Some error messages that show problems with a pair of non-matching values will now
   highlight the differences.
-
-
-Changes from 8.8.2 to 8.9+beta1
-===============================
-
-Kernel
-
-- Mutually defined records are now supported.
-
-Notations
-
-- New support for autonomous grammars of terms, called "custom
-  entries" (see chapter "Syntax extensions" of the reference manual).
-
-- Deprecated compatibility notations will actually be removed in the
-  next version of Coq.  Uses of these notations are generally easy to
-  fix thanks to the hint contained in the deprecation warnings. For
-  projects that require more than a handful of such fixes, there is [a
-  script](https://gist.github.com/JasonGross/9770653967de3679d131c59d42de6d17#file-replace-notations-py)
-  that will do it automatically, using the output of coqc. The script
-  contains documentation on its usage in a comment at the top.
-
-- When several notations are available for the same expression,
-  priority is given to latest notations defined in the scopes being
-  opened, in order, rather than to the latest notations defined
-  independently of whether they are in an opened scope or not.
-
-Tactics
-
-- Added toplevel goal selector `!` which expects a single focused goal.
-  Use with `Set Default Goal Selector` to force focusing before tactics
-  are called.
-
-- The undocumented "nameless" forms `fix N`, `cofix` that were
-  deprecated in 8.8 have been removed from Ltac's syntax; please use
-  `fix ident N/cofix ident` to explicitly name the (co)fixpoint
-  hypothesis to be introduced.
-
-- Introduction tactics `intro`/`intros` on a goal that is an
-  existential variable now force a refinement of the goal into a
-  dependent product rather than failing.
-
-- Support for `fix`/`cofix` added in Ltac `match` and `lazymatch`.
-
-- Ltac backtraces now include trace information about tactics
-  called by OCaml-defined tactics.
-
-- Option `Ltac Debug` now applies also to terms built using Ltac functions.
-
-- Deprecated the `Implicit Tactic` family of commands.
-
-- The default program obligation tactic uses a bounded proof search
-  instead of an unbounded and potentially non-terminating one now
-  (source of incompatibility).
-
-- The `simple apply` tactic now respects the `Opaque` flag when called from
-  Ltac (`auto` still does not respect it).
-
-- Tactic `constr_eq` now adds universe constraints needed for the
-  identity to the context (it used to ignore them). New tactic
-  `constr_eq_strict` checks that the required constraints already hold
-  without adding new ones. Preexisting tactic `constr_eq_nounivs` can
-  still be used if you really want to ignore universe constraints.
-
-- Tactics and tactic notations now understand the `deprecated` attribute.
-- The `fourier` tactic has been removed. Please now use `lra` instead. You
-  may need to add `Require Import Lra` to your developments. For compatibility,
-  we now define `fourier` as a deprecated alias of `lra`.
-
-- The `romega` tactics have been deprecated; please use `lia` instead.
-
-Focusing
-
-- Focusing bracket `{` now supports named goal selectors,
-  e.g. `[x]: {` will focus on a goal (existential variable) named `x`.
-  As usual, unfocus with `}` once the sub-goal is fully solved.
-
-Specification language
-
-- A fix to unification (which was sensitive to the ascii name of
-  variables) may occasionally change type inference in incompatible
-  ways, especially regarding the inference of the return clause of `match`.
-
-Standard Library
-
-- Added `Ascii.eqb` and `String.eqb` and the `=?` notation for them,
-  and proved some lemmas about them.  Note that this might cause
-  incompatibilities if you have, e.g., `string_scope` and `Z_scope` both
-  open with `string_scope` on top, and expect `=?` to refer to `Z.eqb`.
-  Solution: wrap `_ =? _` in `(_ =? _)%Z` (or whichever scope you
-  want).
-
-- Added `Ndigits.N2Bv_sized`, and proved some lemmas about it.
-  Deprecated `Ndigits.N2Bv_gen`.
-
-- The scopes `int_scope` and `uint_scope` have been renamed to
-  `dec_int_scope` and `dec_uint_scope`, to clash less with ssreflect
-  and other packages.  They are still delimited by `%int` and `%uint`.
-
-- Syntax notations for `string`, `ascii`, `Z`, `positive`, `N`, `R`,
-  and `int31` are no longer available merely by `Require`ing the files
-  that define the inductives.  You must `Import` `Coq.Strings.String.StringSyntax`
-  (after `Require` `Coq.Strings.String`), `Coq.Strings.Ascii.AsciiSyntax` (after
-  `Require` `Coq.Strings.Ascii`), `Coq.ZArith.BinIntDef`, `Coq.PArith.BinPosDef`,
-  `Coq.NArith.BinNatDef`, `Coq.Reals.Rdefinitions`, and
-  `Coq.Numbers.Cyclic.Int31.Int31`, respectively, to be able to use
-  these notations.  Note that passing `-compat 8.8` or issuing
-  `Require Import Coq.Compat.Coq88` will make these notations
-  available.  Users wishing to port their developments automatically
-  may download `fix.py` from
-  <https://gist.github.com/JasonGross/5d4558edf8f5c2c548a3d96c17820169>
-  and run a command like `while true; do make -Okj 2>&1 |
-  /path/to/fix.py; done` and get a cup of coffee.  (This command must
-  be manually interrupted once the build finishes all the way though.
-  Note also that this method is not fail-proof; you may have to adjust
-  some scopes if you were relying on string notations not being
-  available even when `string_scope` was open.)
-
-- Numeral syntax for `nat` is no longer available without loading the
-  entire prelude (`Require Import Coq.Init.Prelude`).  This only
-  impacts users running Coq without the init library (`-nois` or
-  `-noinit`) and also issuing `Require Import Coq.Init.Datatypes`.
-
-Tools
-
-- Coq_makefile lets one override or extend the following variables from
-  the command line: `COQFLAGS`, `COQCHKFLAGS`, `COQDOCFLAGS`.
-  `COQFLAGS` is now entirely separate from `COQLIBS`, so in custom Makefiles
-  `$(COQFLAGS)` should be replaced by `$(COQFLAGS) $(COQLIBS)`.
-
-- Removed the `gallina` utility (extracts specification from Coq vernacular files).
-  If you would like to maintain this tool externally, please contact us.
-
-- Removed the Emacs modes distributed with Coq. You are advised to
-  use [Proof-General](https://proofgeneral.github.io/) (and optionally
-  [Company-Coq](https://github.com/cpitclaudel/company-coq)) instead.
-  If your use case is not covered by these alternative Emacs modes,
-  please open an issue. We can help set up external maintenance as part
-  of Proof-General, or independently as part of coq-community.
-
-Vernacular Commands
-
-- Removed deprecated commands `Arguments Scope` and `Implicit Arguments`
-  (not the option). Use the `Arguments` command instead.
-- Nested proofs may be enabled through the option `Nested Proofs Allowed`.
-  By default, they are disabled and produce an error. The deprecation
-  warning which used to occur when using nested proofs has been removed.
-- Added option `Uniform Inductive Parameters` which abstracts over parameters
-  before typechecking constructors, allowing to write for example
-  `Inductive list (A : Type) := nil : list | cons : A -> list -> list.`
-- New `Set Hint Variables/Constants Opaque/Transparent` commands for setting
-  globally the opacity flag of variables and constants in hint databases,
-  overwritting the opacity set of the hint database.
-- Added generic syntax for "attributes", as in:
-  `#[local] Lemma foo : bar.`
-- Added the `Numeral Notation` command for registering decimal numeral
-  notations for custom types
-- The `Set SsrHave NoTCResolution` command no longer has special global
-  scope. If you want the previous behavior, use `Global Set SsrHave
-  NoTCResolution`.
-- Multiple sections with the same name are allowed.
-
-Coq binaries and process model
-
-- Before 8.9, Coq distributed a single `coqtop` binary and a set of
-  dynamically loadable plugins that used to take over the main loop
-  for tasks such as IDE language server or parallel proof checking.
-
-  These plugins have been turned into full-fledged binaries so each
-  different process has associated a particular binary now, in
-  particular `coqidetop` is the CoqIDE language server, and
-  `coq{proof,tactic,query}worker` are in charge of task-specific and
-  parallel proof checking.
-
-SSReflect
-
-- The implementation of delayed clear switches in intro patterns
-  is now simpler to explain:
-  1. The immediate effect of a clear switch like `{x}` is to rename the
-     variable `x` to `_x_` (i.e. a reserved identifier that cannot be mentioned
-     explicitly)
-  2. The delayed effect of `{x}` is that `_x_` is cleared at the end of the intro
-     pattern
-  3. A clear switch immediately before a view application like `{x}/v` is
-     translated to `/v{x}`.
-
-  In particular, the third rule lets one write `{x}/v` even if `v` uses the variable `x`:
-  indeed the view is executed before the renaming.
-
-- An empty clear switch is now accepted in intro patterns before a
-  view application whenever the view is a variable.
-  One can now write `{}/v` to mean `{v}/v`.  Remark that `{}/x` is very similar
-  to the idiom `{}e` for the rewrite tactic (the equation `e` is used for
-  rewriting and then discarded).
-
-Standard Library
-
-- There are now conversions between `string` and `positive`, `Z`,
-  `nat`, and `N` in binary, octal, and hex.
-
-Display diffs between proof steps
-
-- `coqtop` and `coqide` can now highlight the differences between proof steps
-  in color. This can be enabled from the command line or the
-  `Set Diffs "on"/"off"/"removed"` command. Please see the documentation for
-  details.  Showing diffs in Proof General requires small changes to PG
-  (under discussion).
-
-Notations
-
-- Added `++` infix for `VectorDef.append`.
-  Note that this might cause incompatibilities if you have, e.g., `list_scope`
-  and `vector_scope` both open with `vector_scope` on top, and expect `++` to
-  refer to `app`.
-  Solution: wrap `_ ++ _` in `(_ ++ _)%list` (or whichever scope you want).
-
-Changes from 8.8.1 to 8.8.2
-===========================
-
-Documentation
-
-- A PDF version of the reference manual is available once again.
-
-Tools
-
-- The coq-makefile targets `print-pretty-timed`, `print-pretty-timed-diff`,
-  and `print-pretty-single-time-diff` now correctly label the "before" and
-  "after" columns, rather than swapping them.
-
-Kernel
-
-- The kernel does not tolerate capture of global universes by
-  polymorphic universe binders, fixing a soundness break (triggered
-  only through custom plugins)
-
-Windows installer
-
-- The Windows installer now includes many more external packages that can be
-  individually selected for installation.
-
-Many other bug fixes and lots of documentation improvements (for details,
-see the 8.8.2 milestone at https://github.com/coq/coq/milestone/15?closed=1).
-
-Changes from 8.8.0 to 8.8.1
-===========================
-
-Kernel
-
-- Fix a critical bug with cofixpoints and `vm_compute`/`native_compute` (#7333).
-- Fix a critical bug with modules and algebraic universes (#7695)
-- Fix a critical bug with inlining of polymorphic constants (#7615).
-- Fix a critical bug with universe polymorphism and `vm_compute` (#7723). Was
-  present since 8.5.
-
-Notations
-
-- Fixed unexpected collision between only-parsing and only-printing
-  notations (issue #7462).
-
-Windows installer
-
-- The Windows installer now includes external packages Ltac2 and Equations
-  (it included the Bignums package since 8.8+beta1).
-
-Many other bug fixes, documentation improvements (including fixes of
-regressions due to the Sphinx migration), and user message improvements
-(for details, see the 8.8.1 milestone at
-https://github.com/coq/coq/milestone/13?closed=1).
-
-Changes from 8.8+beta1 to 8.8.0
-===============================
-
-Tools
-
-- Asynchronous proof delegation policy was fixed. Since version 8.7
-  Coq was ignoring previous runs and the `-async-proofs-delegation-threshold`
-  option did not have the expected behavior.
-
-Tactic language
-
-- The undocumented "nameless" forms `fix N`, `cofix` have been
-  deprecated; please use `fix ident N /cofix ident` to explicitely
-  name the (co)fixpoint hypothesis to be introduced.
-
-Documentation
-
-- The reference manual is now fully ported to Sphinx.
-
-Other small deprecations and bug fixes.
-
-Changes from 8.7.2 to 8.8+beta1
-===============================
-
-Kernel
-
-- Support for template polymorphism for definitions was removed. May trigger
-  more "universe inconsistency" errors in rare occasions.
-- Fixpoints are no longer allowed on non-recursive inductive types.
-
-Notations
-
-- Recursive notations with the recursive pattern repeating on the
-  right (e.g. "( x ; .. ; y ; z )") now supported.
-- Notations with a specific level for the leftmost nonterminal,
-  when printing-only, are supported.
-- Notations can now refer to the syntactic category of patterns (as in
-  "fun 'pat =>" or "match p with pat => ... end"). Two variants are
-  available, depending on whether a single variable is considered as a
-  pattern or not.
-- Recursive notations now support ".." patterns with several
-  occurrences of the recursive term or binder, possibly mixing terms
-  and binders, possibly in reverse left-to-right order.
-- "Locate" now working also on notations of the form "x + y" (rather
-  than "_ + _").
-
-Specification language
-
-- When printing clauses of a "match", clauses with same right-hand
-  side are factorized and the last most factorized clause with no
-  variables, if it exists, is turned into a default clause.
-  Use "Unset Printing Allow Default Clause" do deactivate printing
-  of a default clause.
-  Use "Unset Printing Factorizable Match Patterns" to deactivate
-  factorization of clauses with same right-hand side.
-
-Tactics
-
-- On Linux, "native_compute" calls can be profiled using the "perf"
-  utility. The command "Set NativeCompute Profiling" enables
-  profiling, and "Set NativeCompute Profile Filename" customizes
-  the profile filename.
-- The tactic "omega" is now aware of the bodies of context variables
-  such as "x := 5 : Z" (see #1362). This could be disabled via
-  Unset Omega UseLocalDefs.
-- The tactic "romega" is also aware now of the bodies of context variables.
-- The tactic "zify" resp. "omega with N" is now aware of N.pred.
-- Tactic "decide equality" now able to manage constructors which
-  contain proofs.
-- Added tactics reset ltac profile, show ltac profile (and variants)
-- Added tactics restart_timer, finish_timing, and time_constr as an
-  experimental way of timing Ltac's evaluation phase
-- Added tactic optimize_heap, analogous to the Vernacular Optimize
-  Heap, which performs a major garbage collection and heap compaction
-  in the OCaml run-time system.
-- The tactics "dtauto", "dintuition", "firstorder" now handle inductive types
-  with let bindings in the parameters.
-- The tactic "dtauto" now handles some inductives such as
-  "@sigT A (fun _ => B)" as non-dependent conjunctions.
-- A bug fixed in "rewrite H in *" and "rewrite H in * |-" may cause a
-  few rare incompatibilities (it was unintendedly recursively
-  rewriting in the side conditions generated by H).
-- Added tactics "assert_succeeds tac" and "assert_fails tac" to ensure
-  properties of the executation of a tactic without keeping the effect
-  of the execution.
-- `vm_compute` now supports existential variables.
-- Calls to `shelve` and `give_up` within calls to tactic `refine` now working.
-- Deprecated tactic `appcontext` was removed.
-
-Focusing
-
-- Focusing bracket `{` now supports single-numbered goal selector,
-  e.g. `2: {` will focus on the second sub-goal. As usual, unfocus
-  with `}` once the sub-goal is fully solved.
-  The `Focus` and `Unfocus` commands are now deprecated.
-
-Vernacular Commands
-
-- Proofs ending in "Qed exporting ident, .., ident" are not supported
-  anymore. Constants generated during `abstract` are kept private to the
-  local environment.
-- The deprecated Coercion Local, Open Local Scope, Notation Local syntax
-  was removed. Use Local as a prefix instead.
-- For the Extraction Language command, "OCaml" is spelled correctly.
-  The older "Ocaml" is still accepted, but deprecated.
-- Using “Require” inside a section is deprecated.
-- An experimental command "Show Extraction" allows to extract the content
-  of the current ongoing proof (grant wish #4129).
-- Coercion now accepts the type of its argument to be "Prop" or "Type".
-- The "Export" modifier can now be used when setting and unsetting options, and
-  will result in performing the same change when the module corresponding the
-  command is imported.
-- The `Axiom` command does not automatically declare axioms as instances when
-  their type is a class. Previous behavior can be restored using `Set
-  Typeclasses Axioms Are Instances`.
-
-Universes
-
-- Qualified naming of global universes now works like other namespaced
-  objects (e.g. constants), with a separate namespace, inside and across
-  module and library boundaries. Global universe names introduced in an
-  inductive / constant / Let declaration get qualified with the name of
-  the declaration.
-- Universe cumulativity for inductive types is now specified as a
-  variance for each polymorphic universe. See the reference manual for
-  more information.
-- Inference of universe constraints with cumulative inductive types
-  produces more general constraints. Unsetting new option Cumulativity
-  Weak Constraints produces even more general constraints (but may
-  produce too many universes to be practical).
-- Fix #5726: Notations that start with `Type` now support universe instances
-  with `@{u}`.
-- `with Definition` now understands universe declarations
-  (like `@{u| Set < u}`).
-
-Tools
-
-- Coq can now be run with the option -mangle-names to change the auto-generated
-  name scheme. This is intended to function as a linter for developments that
-  want to be robust to changes in auto-generated names. This feature is experimental,
-  and may change or disappear without warning.
-- GeoProof support was removed.
-
-Checker
-
-- The checker now accepts filenames in addition to logical paths.
-
-CoqIDE
-
-- Find and Replace All report the number of occurrences found; Find indicates
-  when it wraps.
-
-coqdep
-
-- Learned to read -I, -Q, -R and filenames from _CoqProject files.
-  This is used by coq_makefile when generating dependencies for .v
-  files (but not other files).
-
-Documentation
-
-- The Coq FAQ, formerly located at https://coq.inria.fr/faq, has been
-  moved to the GitHub wiki section of this repository; the main entry
-  page is https://github.com/coq/coq/wiki/The-Coq-FAQ.
-- Documentation: a large community effort resulted in the migration
-  of the reference manual to the Sphinx documentation tool. The result
-  is partially integrated in this version.
-
-Standard Library
-
-- New libraries Coq.Init.Decimal, Coq.Numbers.DecimalFacts,
-  Coq.Numbers.DecimalNat, Coq.Numbers.DecimalPos,
-  Coq.Numbers.DecimalN, Coq.Numbers.DecimalZ,
-  Coq.Numbers.DecimalString providing a type of decimal numbers, some
-  facts about them, and conversions between decimal numbers and nat,
-  positive, N, Z, and string.
-- Added [Coq.Strings.String.concat] to concatenate a list of strings
-  inserting a separator between each item
-- Notation `'` for Zpos in QArith was removed.
-
-- Some deprecated aliases are now emitting warnings when used.
-
-Compatibility support
-
-- Support for compatibility with versions before 8.6 was dropped.
-
-Options
-
-- The following deprecated options have been removed:
-
-  + `Refolding Reduction`
-  + `Standard Proposition Elimination`
-  + `Dependent Propositions Elimination`
-  + `Discriminate Introduction`
-  + `Shrink Abstract`
-  + `Tactic Pattern Unification`
-  + `Intuition Iff Unfolding`
-  + `Injection L2R Pattern Order`
-  + `Record Elimination Schemes`
-  + `Match Strict`
-  + `Tactic Compat Context`
-  + `Typeclasses Legacy Resolution`
-  + `Typeclasses Module Eta`
-  + `Typeclass Resolution After Apply`
-
-Changes from 8.7.1 to 8.7.2
-===========================
-
-Fixed a critical bug in the VM handling of universes (#6677). This bug
-affected all releases since 8.5.
-
-Improved support for building with OCaml 4.06.0 and external num package.
-
-Many other bug fixes, documentation improvements, and user
-message improvements (for details, see the 8.7.2 milestone at
-https://github.com/coq/coq/milestone/11?closed=1).
-
-Changes from 8.7.0 to 8.7.1
-===========================
-
-Compatibility with OCaml 4.06.0.
-
-Many bug fixes, documentation improvements, and user message improvements (for
-details see the 8.7.1 milestone at https://github.com/coq/coq/milestone/10?closed=1).
-
-Changes from 8.7+beta2 to 8.7.0
-===============================
-
-OCaml
-
-- Users can pass specific flags to the OCaml optimizing compiler by
-  -using the flambda-opts configure-time option.
-
-  Beware that compiling Coq with a flambda-enabled compiler is
-  experimental and may require large amounts of RAM and CPU, see
-  INSTALL for more details.
-
-Changes from 8.7+beta1 to 8.7+beta2
-===================================
-
-Tools
-
-- In CoqIDE, the "Compile Buffer" command takes account of flags in
-  _CoqProject or other project file.
-
-Improvements around some error messages.
-
-Many bug fixes including two important ones:
-
-- Bug #5730: CoqIDE becomes unresponsive on file open.
-- coq_makefile: make sure compile flags for Coq and coq_makefile are in sync
-  (in particular, make sure the `-safe-string` option is used to compile plugins).
-
-Changes from 8.6.1 to 8.7+beta1
-===============================
-
-Tactics
-
-- New tactic "extensionality in H" which applies (possibly dependent)
-  functional extensionality in H supposed to be a quantified equality
-  until giving a bare equality.
-- New tactic "inversion_sigma" which turns equalities of dependent
-  pairs (e.g., "existT P x p = existT P y q", frequently left over by
-  "inversion" on a dependent type family) into pairs of equalities
-  (e.g., a hypothesis "H : x = y" and a hypothesis of type "rew H in p
-  = q"); these hypotheses can subsequently be simplified using
-  "subst", without ever invoking any kind of axiom asserting
-  uniqueness of identity proofs. If you want to explicitly specify the
-  hypothesis to be inverted, or name the generated hypotheses, you can
-  invoke "induction H as [H1 H2] using eq_sigT_rect".  The tactic also
-  works for "sig", "sigT2", and "sig2", and there are similar
-  "eq_sig*_rect" induction lemmas.
-- Tactic "specialize with ..." now accepts any partial bindings.
-  Missing bindings are either solved by unification or left quantified
-  in the hypothesis.
-- New representation of terms that statically ensure stability by
-  evar-expansion. This has several consequences.
-  * In terms of performance, this adds a cost to every term destructuration,
-    but at the same time most eager evar normalizations were removed, which
-    couterbalances this drawback and even sometimes outperforms the old
-    implementation. For instance, many operations that would require O(n)
-    normalization of the term are now O(1) in tactics. YMMV.
-  * This triggers small changes in unification, which was not evar-insensitive.
-    Most notably, the new implementation recognizes Miller patterns that were
-    missed before because of a missing normalization step. Hopefully this should
-    be fairly uncommon.
-- Tactic "auto with real" can now discharge comparisons of literals.
-- The types of variables in patterns of "match" are now
-  beta-iota-reduced after type-checking. This has an impact on the
-  type of the variables that the tactic "refine" introduces in the
-  context, producing types a priori closer to the expectations.
-- In "Tactic Notation" or "TACTIC EXTEND", entry "constr_with_bindings"
-  now uses type classes and rejects terms with unresolved holes, like
-  entry "constr" does. To get the former behavior use
-  "open_constr_with_bindings" (possible source of incompatibility).
-- New e-variants eassert, eenough, epose proof, eset, eremember, epose
-  which behave like the corresponding variants with no "e" but turn
-  unresolved implicit arguments into existential variables, on the
-  shelf, rather than failing.
-- Tactic injection has become more powerful (closes bug #4890) and its
-  documentation has been updated.
-- New variants of the `first` and `solve` tacticals that do not rely
-  on parsing rules, meant to define tactic notations.
-- Added support for side effects hooks in `cbv`, `cbn` and `simpl`.
-  The side effects are provided via a plugin:
-  https://github.com/herbelin/reduction-effects/
-- It is now possible to take hint database names as parameters in a
-  Ltac definition or a Tactic Notation.
-- New option `Set Ltac Batch Debug` on top of `Set Ltac Debug` for
-  non-interactive Ltac debug output.
-
-Gallina
-
-- Now supporting all kinds of binders, including 'pat, in syntax of record fields.
-
-Vernacular Commands
-
-- Goals context can be printed in a more compact way when `Set
-  Printing Compact Contexts` is activated.
-- Unfocused goals can be printed with the `Set Printing Unfocused`
-  option.
-- `Print` now shows the types of let-bindings.
-- The compatibility options for printing primitive projections
-  (`Set Printing Primitive Projection Parameters` and
-  `Set Printing Primitive Projection Compatibility`) are now off by default.
-- Possibility to unset the printing of notations in a more fine grained
-  fashion than `Unset Printing Notations` is provided without any
-  user-syntax. The goal is that someone creates a plugin to experiment
-  such a user-syntax, to be later integrated in Coq when stabilized.
-- `About` now tells if a reference is a coercion.
-- The deprecated `Save` vernacular and its form `Save Theorem id` to
-  close proofs have been removed from the syntax. Please use `Qed`.
-- `Search` now sorts results by relevance (the relevance metric is a
-  weighted sum of number of distinct symbols and size of the term).
-
-Standard Library
-
-- New file PropExtensionality.v to explicitly work in the axiomatic
-  context of propositional extensionality.
-- New file SetoidChoice.v axiomatically providing choice over setoids,
-  and, consequently, choice of representatives in equivalence classes.
-  Various proof-theoretic characterizations of choice over setoids in
-  file ChoiceFacts.v.
-- New lemmas about iff and about orders on positive and Z.
-- New lemmas on powerRZ.
-- Strengthened statement of JMeq_eq_dep (closes bug #4912).
-- The BigN, BigZ, BigZ libraries are no longer part of the Coq standard
-  library, they are now provided by a separate repository
-    https://github.com/coq/bignums
-  The split has been done just after the Int31 library.
-
-- IZR (Reals) has been changed to produce a compact representation of
-  integers. As a consequence, IZR is no longer convertible to INR and
-  lemmas such as INR_IZR_INZ should be used instead.
-- Real constants are now represented using IZR rather than R0 and R1;
-  this might cause rewriting rules to fail to apply to constants.
-- Added new notation {x & P} for sigT (without a type for x)
-
-Plugins
-
-- The Ssreflect plugin is now distributed with Coq. Its documentation has
-  been integrated as a chapter of the reference manual. This chapter is
-  work in progress so feedback is welcome.
-- The mathematical proof language (also known as declarative mode) was removed.
-- A new command Extraction TestCompile has been introduced, not meant
-  for the general user but instead for Coq's test-suite.
-- The extraction plugin is no longer loaded by default. It must be
-  explicitly loaded with [Require Extraction], which is backwards
-  compatible.
-- The functional induction plugin (which provides the [Function]
-  vernacular) is no longer loaded by default. It must be explicitly
-  loaded with [Require FunInd], which is backwards compatible.
-
-
-Dependencies
-
-- Support for camlp4 has been removed.
-
-Tools
-
-- coq_makefile was completely redesigned to improve its maintainability and
-  the extensibility of generated Makefiles, and to make _CoqProject files
-  more palatable to IDEs.  Overview:
-  * _CoqProject files contain only Coq specific data (i.e. the list of
-    files, -R options, ...)
-  * coq_makefile translates _CoqProject to Makefile.conf and copies in the
-    desired location a standard Makefile (that reads Makefile.conf)
-  * Makefile extensions can be implemented in a Makefile.local file (read
-    by the main Makefile) by installing a hook in the extension points
-    provided by the standard Makefile
-  The current version contains code for retro compatibility that prints
-  warnings when a deprecated feature is used.  Please upgrade your _CoqProject
-  accordingly.
-  * Additionally, coq_makefile-made Makefiles now support experimental timing
-    targets `pretty-timed`, `pretty-timed-before`, `pretty-timed-after`,
-    `print-pretty-timed-diff`, `print-pretty-single-time-diff`,
-    `all.timing.diff`, and the variable `TIMING=1` (or `TIMING=before` or
-    `TIMING=after`); see the documentation for more details.
-
-Build Infrastructure
-
-- Note that 'make world' does not build the bytecode binaries anymore.
-  For that, you can use 'make byte' (and 'make install-byte' afterwards).
-  Warning: native and byte compilations should *not* be mixed in the same
-  instance of 'make -j', otherwise both ocamlc and ocamlopt might race for
-  access to the same .cmi files. In short, use "make -j && make -j byte"
-  instead of "make -j world byte".
-
-Universes
-
-- Cumulative inductive types. see prefixes "Cumulative", "NonCumulative"
-  for inductive definitions and the option "Set Polymorphic Inductive Cumulativity"
-  in the reference manual.
-- New syntax `foo@{_}` to instantiate a polymorphic definition with
-  anonymous universes (can also be used with `Type`).
-
-XML Protocol and internal changes
-
-See dev/doc/changes.txt
-
-Many bugfixes including #1859, #2884, #3613, #3943, #3994,
-#4250, #4709, #4720, #4824, #4844, #4911, #5026, #5233,
-#5275, #5315, #5336, #5360, #5390, #5414, #5417, #5420,
-#5439, #5449, #5475, #5476, #5482, #5501, #5507, #5520,
-#5523, #5524, #5553, #5577, #5578, #5589, #5597, #5598,
-#5607, #5618, #5619, #5620, #5641, #5648, #5651, #5671.
-
-Many bugfixes on OS X and Windows (now the test-suite passes on these
-platforms too).
-
-Many optimizations.
-
-Many documentation improvements.
-
-Changes from 8.6 to 8.6.1
-=========================
-
-- Fix #5380: Default colors for CoqIDE are actually applied.
-- Fix plugin warnings
-- Document named evars (including Show ident)
-- Fix Bug #5574, document function scope
-- Adding a test case as requested in bug 5205.
-- Fix Bug #5568, no dup notation warnings on repeated module imports
-- Fix documentation of Typeclasses eauto :=
-- Refactor documentation of records.
-- Protecting from warnings while compiling 8.6
-- Fixing an inconsistency between configure and configure.ml
-- Add test-suite checks for coqchk with constraints
-- Fix bug #5019 (looping zify on dependent types)
-- Fix bug 5550: "typeclasses eauto with" does not work with section variables.
-- Bug 5546, qualify datatype constructors when needed in Show Match
-- Bug #5535, test for Show with -emacs
-- Fix bug #5486, don't reverse ids in tuples
-- Fixing #5522 (anomaly with free vars of pat)
-- Fix bug #5526, don't check for nonlinearity in notation if printing only
-- Fix bug #5255
-- Fix bug #3659: -time should understand multibyte encodings.
-- FIx bug #5300: Anomaly: Uncaught exception Not_found" in "Print Assumptions".
-- Fix outdated description in RefMan.
-- Repairing `Set Rewriting Schemes`
-- Fixing #5487 (v8.5 regression on ltac-matching expressions with evars).
-- Fix description of command-line arguments for Add (Rec) LoadPath
-- Fix bug #5377: @? patterns broken.
-- add XML protocol doc
-- Fix anomaly when doing [all:Check _.] during a proof.
-- Correction of bug #4306
-- Fix #5435: [Eval native_compute in] raises anomaly.
-- Instances should obey universe binders even when defined by tactics.
-- Intern names bound in match patterns
-- funind: Ignore missing info for current function
-- Do not typecheck twice the type of opaque constants.
-- show unused intro pattern warning
-- [future] Be eager when "chaining" already resolved future values.
-- Opaque side effects
-- Fix #5132: coq_makefile generates incorrect install goal
-- Run non-tactic comands without resilient_command
-- Univs: fix bug #5365, generation of u+k <= v constraints
-- make `emit' tail recursive
-- Don't require printing-only notation to be productive
-- Fix the way setoid_rewrite handles bindings.
-- Fix for bug 5244 - set printing width ignored when given enough space
-- Fix bug 4969, autoapply was not tagging shelved subgoals correctly
-
-Changes from V8.6beta1 to V8.6
-==============================
-
-Kernel
-
-- Fixed critical bug #5248 in VM long multiplication on 32-bit
-  architectures. Was there only since 8.6beta1, so no stable release impacted.
-
-Other bug fixes in universes, type class shelving,...
-
-Changes from V8.5 to V8.6beta1
-==============================
-
-Kernel
-
-- A new, faster state-of-the-art universe constraint checker.
-
-Specification language
-
-- Giving implicit arguments explicitly to a constant with multiple
-  choices of implicit arguments does not break any more insertion of
-  further maximal implicit arguments.
-- Ability to put any pattern in binders, prefixed by quote, e.g.
-  "fun '(a,b) => ...", "λ '(a,(b,c)), ...", "Definition foo '(x,y) := ...".
-  It expands into a "let 'pattern := ..."
-
-Tactics
-
-- Flag "Bracketing Last Introduction Pattern" is now on by default.
-- Flag "Regular Subst Tactic" is now on by default: it respects the
-  initial order of hypothesis, it contracts cycles, it unfolds no
-  local definitions (common source of incompatibilities, fixable by
-  "Unset Regular Subst Tactic").
-- New flag "Refolding Reduction", now disabled by default, which turns
-  on refolding of constants/fixpoints (as in cbn) during the reductions
-  done during type inference and tactic retyping. Can be extremely
-  expensive. When set off, this recovers the 8.4 behaviour of unification
-  and type inference. Potential source of incompatibility with 8.5 developments
-  (the option is set on in Compat/Coq85.v).
-- New flag "Shrink Abstract" that minimalizes proofs generated by the abstract
-  tactical w.r.t. variables appearing in the body of the proof.
-  On by default and deprecated. Minor source of incompatibility
-  for code relying on the precise arguments of abstracted proofs.
-- Serious bugs are fixed in tactic "double induction" (source of
-  incompatibilities as soon as the inductive types have dependencies in
-  the type of their constructors; "double induction" remains however
-  deprecated).
-- In introduction patterns of the form (pat1,...,patn), n should match
-  the exact number of hypotheses introduced (except for local definitions
-  for which pattern can be omitted, as in regular pattern-matching).
-- Tactic scopes in Ltac like constr: and ltac: now require parentheses around
-  their argument.
-- Every generic argument type declares a tactic scope of the form "name:(...)"
-  where name is the name of the argument. This generalizes the constr: and ltac:
-  instances.
-- When in strict mode (i.e. in a Ltac definition), if the "intro" tactic is
-  given a free identifier, it is not bound in subsequent tactics anymore.
-  In order to introduce a binding, use e.g. the "fresh" primitive instead
-  (potential source of incompatibilities).
-- New tactics is_ind, is_const, is_proj, is_constructor for use in Ltac.
-- New goal selectors.  Sets of goals can be selected by listing integers
-  ranges. Example: "1,4-7,24: tac" focuses "tac" on goals 1,4,5,6,7,24.
-- For uniformity with "destruct"/"induction" and for a more natural
-  behavior, "injection" can now work in place by activating option
-  "Structural Injection". In this case, hypotheses are also put in the
-  context in the natural left-to-right order and the hypothesis on
-  which injection applies is cleared.
-- Tactic "contradiction" (hence "easy") now also solve goals with
-  hypotheses of the form "~True" or "t<>t" (possible source of
-  incompatibilities because of more successes in automation, but
-  generally a more intuitive strategy).
-- Option "Injection On Proofs" was renamed "Keep Proof Equalities". When
-  enabled, injection and inversion do not drop equalities between objects
-  in Prop. Still disabled by default.
-- New tactics "notypeclasses refine" and "simple notypeclasses refine" that
-  disallow typeclass resolution when typechecking their argument, for use
-  in typeclass hints.
-- Integration of LtacProf, a profiler for Ltac.
-- Reduction tactics now accept more fine-grained flags: iota is now a shorthand
-  for the new flags match, fix and cofix.
-- The ssreflect subterm selection algorithm is now accessible to tactic writers
-  through the ssrmatching plugin.
-- When used as an argument of an ltac function, "auto" without "with"
-  nor "using" clause now correctly uses only the core hint database by
-  default.
-
-Hints
-
-- Revised the syntax of [Hint Cut] to follow standard notation for regexps.
-- Hint Mode now accepts "!" which means that the mode matches only if the
-  argument's head is not an evar (it goes under applications, casts, and
-  scrutinees of matches and projections).
-- Hints can now take an optional user-given pattern, used only by
-  [typeclasses eauto] with the [Filtered Unification] option on.
-
-Typeclasses
-
-- Many new options and new engine based on the proof monad. The
-  [typeclasses eauto] tactic is now a multi-goal, multi-success tactic.
-  See reference manual for more information. It is planned to
-  replace auto and eauto in the following version. The 8.5 resolution
-  engine is still available to help solve compatibility issues.
-
-Program
-
-- The "Shrink Obligations" flag now applies to all obligations, not only
-  those solved by the automatic tactic.
-- "Shrink Obligations" is on by default and deprecated. Minor source of
-  incompatibility for code relying on the precise arguments of
-  obligations.
-
-Notations
-
-- "Bind Scope" can once again bind "Funclass" and "Sortclass".
-
-General infrastructure
-
-- New configurable warning system which can be controlled with the vernacular
-  command "Set Warnings", or, under coqc/coqtop, with the flag "-w". In
-  particular, the default is now that warnings are printed by coqc.
-- In asynchronous mode, Coq is now capable of recovering from errors and
-  continue processing the document.
-
-Tools
-
-- coqc accepts a -o option to specify the output file name
-- coqtop accepts --print-version to print Coq and OCaml versions in
-  easy to parse format
-- Setting [Printing Dependent Evars Line] can be unset to disable the
-  computation associated with printing the "dependent evars: " line in
-  -emacs mode
-- Removed the -verbose-compat-notations flag and the corresponding Set
-  Verbose Compat vernacular, since these warnings can now be silenced or
-  turned into errors using "-w".
-
-XML protocol
-
-- message format has changed, see dev/doc/changes.txt for more details.
-
-Many bug fixes, minor changes and documentation improvements are not mentioned
-here.
-
-Changes from V8.5pl2 to V8.5pl3
-===============================
-
-Critical bugfix
-
-- #4876: Guard checker incompleteness when using primitive projections
-
-Other bugfixes
-
-- #4780: Induction with universe polymorphism on was creating ill-typed terms.
-- #4673: regression in setoid_rewrite, unfolding let-ins for type unification.
-- #4754: Regression in setoid_rewrite, allow postponed unification problems to remain.
-- #4769: Anomaly with universe polymorphic schemes defined inside sections.
-- #3886: Program: duplicate obligations of mutual fixpoints.
-- #4994: Documentation typo.
-- #5008: Use the "md5" command on OpenBSD.
-- #5007: Do not assume the "TERM" environment variable is always set.
-- #4606: Output a break before a list only if there was an empty line.
-- #5001: metas not cleaned properly in clenv_refine_in.
-- #2336: incorrect glob data for module symbols (bug #2336).
-- #4832: Remove extraneous dot in error message.
-- Anomaly in printing a unification error message.
-- #4947: Options which take string arguments are not backwards compatible.
-- #4156: micromega cache files are now hidden files.
-- #4871: interrupting par:abstract kills coqtop.
-- #5043: [Admitted] lemmas pick up section variables.
-- Fix name of internal refine ("simple refine").
-- #5062: probably a typo in Strict Proofs mode.
-- #5065: Anomaly: Not a proof by induction.
-- Restore native compiler optimizations, they were disabled since 8.5!
-- #5077: failure on typing a fixpoint with evars in its type.
-- Fix recursive notation bug.
-- #5095: non relevant too strict test in let-in abstraction.
-- Ensuring that the evar name is preserved by "rename".
-- #4887: confusion between using and with in documentation of firstorder.
-- Bug in subst with let-ins.
-- #4762: eauto weaker than auto.
-- Remove if_then_else (was buggy). Use tryif instead.
-- #4970: confusion between special "{" and non special "{{" in notations.
-- #4529: primitive projections unfolding.
-- #4416: Incorrect "Error: Incorrect number of goals".
-- #4863: abstract in typeclass hint fails.
-- #5123: unshelve can impact typeclass resolution
-- Fix a collision about the meta-variable ".." in recursive notations.
-- Fix printing of info_auto.
-- #3209: Not_found due to an occur-check cycle.
-- #5097: status of evars refined by "clear" in ltac: closed wrt evars.
-- #5150: Missing dependency of the test-suite subsystems in prerequisite.
-- Fix a bug in error printing of unif constraints
-- #3941: Do not stop propagation of signals when Coq is busy.
-- #4822: Incorrect assertion in cbn.
-- #3479 parsing of "{" and "}" when a keyword starts with "{" or "}".
-- #5127: Memory corruption with the VM.
-- #5102: bullets parsing broken by calls to parse_entry.
-
-Various documentation improvements
-
-
-Changes from V8.5pl1 to V8.5pl2
-===============================
-
-Critical bugfix
-- Checksums of .vo files dependencies were not correctly checked.
-- Unicode-to-ASCII translation was not injective, leading in a soundness bug in
-  the native compiler.
-
-Other bugfixes
-
-- #4097: more efficient occur-check in presence of primitive projections
-- #4398: type_scope used consistently in "match goal".
-- #4450: eauto does not work with polymorphic lemmas
-- #4677: fix alpha-conversion in notations needing eta-expansion.
-- Fully preserve initial order of hypotheses in "Regular Subst Tactic" mode.
-- #4644: a regression in unification.
-- #4725: Function (Error: Conversion test raised an anomaly) and Program
-  (Error: Cannot infer this placeholder of type)
-- #4747: Problem building Coq 8.5pl1 with OCaml 4.03.0: Fatal warnings
-- #4752: CoqIDE crash on files not ended by ".v".
-- #4777: printing inefficiency with implicit arguments
-- #4818: "Admitted" fails due to undefined universe anomaly after calling
-  "destruct"
-- #4823: remote counter: avoid thread race on sockets
-- #4841: -verbose flag changed semantics in 8.5, is much harder to use
-- #4851: [nsatz] cannot handle duplicated hypotheses
-- #4858: Anomaly: Uncaught exception Failure("hd"). Please report. in variant
-  of nsatz
-- #4880: [nsatz_compute] generates invalid certificates if given redundant
-  hypotheses
-- #4881: synchronizing "Declare Implicit Tactic" with backtrack.
-- #4882: anomaly with Declare Implicit Tactic on hole of type with evars
-- Fix use of "Declare Implicit Tactic" in refine.
-  triggered by CoqIDE
-- #4069, #4718: congruence fails when universes are involved.
-
-Universes
-- Disallow silently dropping universe instances applied to variables
-  (forward compatible)
-- Allow explicit universe instances on notations, when they can apply
-  to the head reference of their expansion.
-
-Build infrastructure
-- New update on how to find camlp5 binary and library at configure time.
-
-Changes from V8.5 to V8.5pl1
-============================
-
-Critical bugfix
-- The subterm relation for the guard condition was incorrectly defined on
-  primitive projections (#4588)
-
-Plugin development tools
-- add a .merlin target to the makefile
-
-Various performance improvements (time, space used by .vo files)
-
-Other bugfixes
-
-- Fix order of arguments to Big.compare_case in ExtrOcamlZBigInt.v
-- Added compatibility coercions from Specif.v which were present in Coq 8.4.
-- Fixing a source of inefficiency and an artificial dependency in the printer in the congruence tactic.
-- Allow to unset the refinement mode of Instance in ML
-- Fixing an incorrect use of prod_appvect on a term which was not a product in setoid_rewrite.
-- Add -compat 8.4 econstructor tactics, and tests
-- Add compatibility Nonrecursive Elimination Schemes
-- Fixing the "No applicable tactic" non informative error message regression on apply.
-- Univs: fix get_current_context (bug #4603, part I)
-- Fix a bug in Program coercion code
-- Fix handling of arity of definitional classes.
-- #4630: Some tactics are 20x slower in 8.5 than 8.4.
-- #4627: records with no declared arity can be template polymorphic.
-- #4623: set tactic too weak with universes (regression)
-- Fix incorrect behavior of CS resolution
-- #4591: Uncaught exception in directory browsing.
-- CoqIDE is more resilient to initialization errors.
-- #4614: "Fully check the document" is uninterruptable.
-- Try eta-expansion of records only on non-recursive ones
-- Fix bug when a sort is ascribed to a Record
-- Primitive projections: protect kernel from erroneous definitions.
-- Fixed bug #4533 with previous Keyed Unification commit
-- Win: kill unreliable hence do not waitpid after kill -9 (Close #4369)
-- Fix strategy of Keyed Unification
-- #4608: Anomaly "output_value: abstract value (outside heap)".
-- #4607: do not read native code files if native compiler was disabled.
-- #4105: poor escaping in the protocol between CoqIDE and coqtop.
-- #4596: [rewrite] broke in the past few weeks.
-- #4533 (partial): respect declared global transparency of projections in unification.ml
-- #4544: Backtrack on using full betaiota reduction during keyed unification.
-- #4540: CoqIDE bottom progress bar does not update.
-- Fix regression from 8.4 in reflexivity
-- #4580: [Set Refine Instance Mode] also used for Program Instance.
-- #4582: cannot override notation [ x ]. MAY CREATE INCOMPATIBILITIES, see #4683.
-- STM: Print/Extraction have to be skipped if -quick
-- #4542: CoqIDE: STOP button also stops workers
-- STM: classify some variants of Instance as regular `Fork nodes.
-- #4574: Anomaly: Uncaught exception Invalid_argument("splay_arity").
-- Do not give a name to anonymous evars anymore. See bug #4547.
-- STM: always stock in vio files the first node (state) of a proof
-- STM: not delegate proofs that contain Vernac(Module|Require|Import), #4530
-- Don't fail fatally if PATH is not set.
-- #4537: Coq 8.5 is slower in typeclass resolution.
-- #4522: Incorrect "Warning..." on windows.
-- #4373: coqdep does not know about .vio files.
-- #3826: "Incompatible module types" is uninformative.
-- #4495: Failed assertion in metasyntax.ml.
-- #4511: evar tactic can create non-typed evars.
-- #4503: mixing universe polymorphic and monomorphic variables and definitions in sections is unsupported.
-- #4519: oops, global shadowed local universe level bindings.
-- #4506: Anomaly: File "pretyping/indrec.ml", line 169, characters 14-20: Assertion failed.
-- #4548: Coqide crashes when going back one command
-
-Changes from V8.5beta3 to V8.5
-==============================
-
-Tools
-
-- Flag "-compat 8.4" now loads Coq.Compat.Coq84. The standard way of
-  putting Coq in v8.4 compatibility mode is to pass the command line flag
-  "-compat 8.4". It can be followed by "-require Coq.Compat.AdmitAxiom"
-  if the 8.4 behavior of admit is needed, in which case it uses an axiom.
-
-Specification language
-
-- Syntax "$(tactic)$" changed to "ltac:(tactic)".
-
-Tactics
-
-- Syntax "destruct !hyp" changed to "destruct (hyp)", and similarly
-  for induction (rare source of incompatibilities easily solvable by
-  removing parentheses around "hyp" when not for the purpose of keeping
-  the hypothesis).
-- Syntax "p/c" for on-the-fly application of a lemma c before
-  introducing along pattern p changed to p%c1..%cn. The feature and
-  syntax are in experimental stage.
-- "Proof using" does not clear unused section variables.
-- Tactic "refine" has been changed back to the 8.4 behavior of shelving subgoals
-  that occur in other subgoals. The "refine" tactic of 8.5beta3 has been
-  renamed "simple refine"; it does not shelve any subgoal.
-- New tactical "unshelve tac" which grab existential variables put on
-  the tactic shelve by the execution of "tac".
-
-Changes from V8.5beta2 to V8.5beta3
-===================================
-
-Vernacular commands
-
-- New command "Redirect" to redirect the output of a command to a file.
-- New command "Undelimit Scope" to remove the delimiter of a scope.
-- New option "Strict Universe Declaration", set by default. It enforces the
-  declaration of all polymorphic universes appearing in a definition when
-  introducing it.
-- New command "Show id" to show goal named id.
-- Option "Virtual Machine" removed.
-
-Tactics
-
-- New flag "Regular Subst Tactic" which fixes "subst" in situations where
-  it failed to substitute all substitutable equations or failed to simplify
-  cycles, or accidentally unfolded local definitions (flag is off by default).
-- New flag "Loose Hint Behavior" to handle hints loaded but not imported in a
-  special way. It accepts three distinct flags:
-  * "Lax", which is the default one, sets the old behavior, i.e. a non-imported
-  hint behaves the same as an imported one.
-  * "Warn" outputs a warning when a non-imported hint is used. Note that this is
-  an over-approximation, because a hint may be triggered by an eauto run that
-  will eventually fail and backtrack.
-  * "Strict" changes the behavior of an unloaded hint to the one of the fail
-  tactic, allowing to emulate the hopefully future import-scoped hint mechanism.
-- New compatibility flag "Universal Lemma Under Conjunction" which
-  let tactics working under conjunctions apply sublemmas of the form
-  "forall A, ... -> A".
-- New compatibility flag "Bracketing Last Introduction Pattern" which can be
-  set so that the last disjunctive-conjunctive introduction pattern given to
-  "intros" automatically complete the introduction of its subcomponents, as the
-  the disjunctive-conjunctive introduction patterns in non-terminal position
-  already do.
-- New flag "Shrink Abstract" that minimalizes proofs generated by the abstract
-  tactical w.r.t. variables appearing in the body of the proof.
-
-Program
-
-- The "Shrink Obligations" flag now applies to all obligations, not only those
-solved by the automatic tactic.
-- Importing Program no longer overrides the "exists" tactic (potential source
-  of incompatibilities).
-- Hints costs are now correctly taken into account (potential source of
-  incompatibilities).
-- Documented the Hint Cut command that allows control of the
-  proof-search during typeclass resolution (see reference manual).
-
-API
-
-- Some functions from pretyping/typing.ml and their derivatives were potential
-  source of evarmap leaks, as they dropped their resulting evarmap. The
-  situation was clarified by renaming them according to a unsafe_* scheme. Their
-  sound variant is likewise renamed to their old name. The following renamings
-  were made.
-  * Typing.type_of -> unsafe_type_of
-  * Typing.e_type_of -> type_of
-  * A new e_type_of function that matches the e_ prefix policy
-  * Tacmach.pf_type_of -> pf_unsafe_type_of
-  * A new safe pf_type_of function.
-  All uses of unsafe_* functions should be eventually eliminated.
-
-Tools
-
-- Added an option -w to control the output of coqtop warnings.
-- Configure now takes an optional -native-compiler (yes|no) flag replacing
-  -no-native-compiler. The new flag is set to no by default under Windows.
-- Flag -no-native-compiler was removed and became the default for coqc. If
-  precompilation of files for native conversion test is desired, use
-  -native-compiler.
-- The -compile command-line option now takes the full path of the considered
-  file, including the ".v" extension, and outputs a warning if such an extension
-  is lacking.
-- The -require and -load-vernac-object command-line options now take a logical
-  path of a given library rather than a physical path, thus they behave like
-  Require [Import] path.
-- The -vm command-line option has been removed.
-
-Standard Library
-
- - There is now a Coq.Compat.Coq84 library, which sets the various compatibility
-   options and does a few redefinitions to make Coq behave more like Coq v8.4.
-   The standard way of putting Coq in v8.4 compatibility mode is to pass the command
-   line flags "-require Coq.Compat.Coq84 -compat 8.4".
-
-Changes from V8.5beta1 to V8.5beta2
-===================================
-
-Logic
-
-- The VM now supports inductive types with up to 8388851 non-constant
-  constructors and up to 8388607 constant ones.
-
-Specification language
-
-- Syntax "$(tactic)$" changed to "ltac: tactic".
-
-Tactics
-
-- A script using the admit tactic can no longer be concluded by either
-  Qed or Defined. In the first case, Admitted can be used instead. In
-  the second case, a subproof should be used.
-- The easy tactic and the now tactical now have a more predictable
-  behavior, but they might now discharge some previously unsolved goals.
-
-Extraction
-
-- Definitions extracted to Haskell GHC should no longer randomly
-  segfault when some Coq types cannot be represented by Haskell types.
-- Definitions can now be extracted to Json for post-processing.
-
-Tools
-
-- Option -I -as has been removed, and option -R -as has been
-  deprecated. In both cases, option -R can be used instead.
-- coq_makefile now generates double-colon rules for rules such as clean.
-
-API
-
-- The interface of [change] has changed to take a [change_arg], which
-  can be built from a [constr] using [make_change_arg].
-
-Changes from V8.4 to V8.5beta1
-==============================
-
-Logic
-
-- Primitive projections for records allow for a compact representation
-  of projections, without parameters and avoid the behavior of defined
-  projections that can unfold to a case expression. To turn the use of
-  native projections on, use [Set Primitive Projections]. Record,
-  Class and Structure types defined while this option is set will be
-  defined with primitive projections instead of the usual encoding as
-  a case expression. For compatibility, when p is a primitive
-  projection, @p can be used to refer to the projection with explicit
-  parameters, i.e. [@p] is definitionally equal to [λ params r. r.(p)].
-  Records with primitive projections have eta-conversion, the
-  canonical form being [mkR pars (p1 t) ... (pn t)].
-- New universe polymorphism (see reference manual)
-- New option -type-in-type to collapse the universe hierarchy (this makes the
-  logic inconsistent).
-- The guard condition for fixpoints is now a bit stricter. Propagation
-  of subterm value through pattern matching is restricted according to
-  the return predicate. Restores compatibility of Coq's logic with the
-  propositional extensionality axiom. May create incompatibilities in
-  recursive programs heavily using dependent types.
-- Trivial inductive types are no longer defined in Type but in Prop, which
-  leads to a non-dependent induction principle being generated in place of
-  the dependent one. To recover the old behavior, explicitly define your
-  inductive types in Set.
-
-Vernacular commands
-
-- A command "Variant" allows to define non-recursive variant types.
-- The command "Record foo ..." does not generate induction principles
-  (foo_rect, foo_rec, foo_ind) anymore by default (feature wish
-  #2693). The command "Variant foo ..." does not either. A flag
-  "Set/Unset Nonrecursive Elimination Schemes" allows changing this.
-  The tactic "induction" on a "Record" or a "Variant" is now actually
-  doing "destruct".
-- The "Open Scope" command can now be given also a delimiter (e.g. Z).
-- The "Definition" command now allows the "Local" modifier, allowing
-  for non-importable definitions. The same goes for "Axiom" and "Parameter".
-- Section-specific commands such as "Let" (resp. "Variable", "Hypothesis") used
-  out of a section now behave like the corresponding "Local" command, i.e.
-  "Local Definition" (resp. "Local Parameter", "Local Axiom"). (potential source
-  of rare incompatibilities).
-- The "Let" command can now define local (co)fixpoints.
-- Command "Search" has been renamed into "SearchHead". The command
-  name "Search" now behaves like former "SearchAbout". The latter name
-  is deprecated.
-- "Search", "About", "SearchHead", "SearchRewrite" and "SearchPattern"
-  now search for hypothesis (of the current goal by default) first.
-  They now also support the goal selector prefix to specify another
-  goal to search: e.g. "n:Search id". This is also true for
-  SearchAbout although it is deprecated.
-- The coq/user-contrib directory and the XDG directories are no longer
-  recursively added to the load path, so files from installed libraries
-  now need to be fully qualified for the "Require" command to find them.
-  The tools/update-require script can be used to convert a development.
-- A new Print Strategies command allows visualizing the opacity status
-  of the whole engine.
-- The "Locate" command now searches through all sorts of qualified namespaces of
-  Coq: terms, modules, tactics, etc. The old behavior of the command can be
-  retrieved using the "Locate Term" command.
-- New "Derive" command to help writing program by derivation.
-- New "Refine Instance Mode" option that allows to deactivate the generation of
-  obligations in incomplete typeclass instances, raising an error instead.
-- "Collection" command to name sets of section hypotheses.  Named collections
-  can be used in the syntax of "Proof using" to assert which section variables
-  are used in a proof.
-- The "Optimize Proof" command can be placed in the middle of a proof to
-  force the compaction of the data structure used to represent the ongoing
-  proof (evar map). This may result in a lower memory footprint and speed up
-  the execution of the following tactics.
-- "Optimize Heap" command to tell the OCaml runtime to perform a major
-  garbage collection step and heap compaction.
-- "Instance" no longer treats the {|...|} syntax specially; it handles it
-  in the same way as other commands, e.g. "Definition". Use the {...}
-  syntax (no pipe symbols) to recover the old behavior.
-
-Specification Language
-
-- Slight changes in unification error messages.
-- Added a syntax $(...)$ that allows putting tactics in terms (may
-  break user notations using "$(", fixable by inserting a space or
-  rewriting the notation).
-- Constructors in pattern-matching patterns now respect the same rules
-  regarding implicit arguments as in applicative position. The old
-  behavior can be recovered by the command "Set Asymmetric
-  Patterns". As a side effect, notations for constructors explicitly
-  mentioning non-implicit parameters can now be used in patterns.
-  Considering that the pattern language is already rich enough, binding
-  local definitions is however now forbidden in patterns (source of
-  incompatibilities for local definitions that delta-reduce to a constructor).
-- Type inference algorithm now granting opacity of constants. This might also
-  affect behavior of tactics (source of incompatibilities, solvable by
-  re-declaring transparent constants which were set opaque).
-- Existential variables are now referred to by an identifier and the
-  relevant part of their instance is displayed by default. They can be
-  reparsed. The naming policy is yet unstable and subject to changes
-  in future releases.
-
-Tactics
-
-- New tactic engine allowing dependent subgoals, fully backtracking
-  (also known as multiple success) tactics, as well as tactics which
-  can consider multiple goals together. In the new tactic engine,
-  instantiation information of existential variables is always
-  propagated to tactics, removing the need to manually use the
-  "instantiate" tactics to mark propagation points.
-  * New tactical (a+b) inserts a backtracking point. When (a+b);c fails
-    during the execution of c, it can backtrack and try b instead of a.
-  * New tactical (once a) removes all the backtracking points from a
-    (i.e. it selects the first success of a).
-  * Tactic "constructor" is now fully backtracking. In case of
-    incompatibilities (e.g. combinatoric explosion), the former
-    behavior of "constructor" can be retrieved by using instead
-    "[> once constructor ..]". Thanks to backtracking, undocumented
-    "constructor <tac>" syntax is now equivalent to
-    "[> once (constructor; tac) ..]".
-  * New "multimatch" variant of "match" tactic which backtracks to
-    new branches in case of a later failure. The "match" tactic is
-    equivalent to "once multimatch".
-  * New selector "all:" such that "all:tac" applies tactic "tac" to
-    all the focused goals, instead of just the first one as is the
-    default.
-  * A corresponding new option Set Default Goal Selector "all" makes
-    the tactics in scripts be applied to all the focused goal by default
-  * New selector "par:" such that "par:tac" applies the (terminating)
-    tactic "tac" to all the focused goal in parallel. The number of worker
-    can be selected with -async-proofs-tac-j and also limited using the
-    coqworkmgr utility.
-  * New tactics "revgoals", "cycle" and "swap" to reorder goals.
-  * The semantics of recursive tactics (introduced with "Ltac t := ..."
-    or "let rec t := ... in ...") changed slightly as t is now
-    applied to every goal, not each goal independently. In particular
-    it may be applied when no goals are left. This may cause tactics
-    such as "let rec t := constructor;t" to loop indefinitely. The
-    simple fix is to rewrite the recursive calls as follows:
-    "let rec t := constructor;[t..]" which recovers the earlier behavior
-    (source of rare incompatibilities).
-  * New tactic language feature "numgoals" to count number of goals. It is
-    accompanied by a "guard" tactic which fails if a Boolean test over
-    integers does not pass.
-  * New tactical "[> ... ]" to apply tactics to individual goals.
-  * New tactic "gfail" which works like "fail" except it will also
-    fail if every goal has been solved.
-  * The refine tactic is changed not to use an ad hoc typing algorithm
-    to generate subgoals. It also uses the dependent subgoal feature
-    to generate goals to materialize every existential variable which
-    is introduced by the refinement (source of incompatibilities).
-  * A tactic shelve is introduced to manage the subgoals which may be
-    solved by unification: shelve removes every goal it is applied to
-    from focus. These goals can later be called back into focus by the
-    Unshelve command.
-  * A variant shelve_unifiable only removes those goals which appear
-    as existential variables in other goals. To emulate the old
-    refine, use "refine c;shelve_unifiable". This can still cause
-    incompatibilities in rare occasions.
-  * New "give_up" tactic to skip over a goal.  A proof containing
-    given up goals cannot be closed with "Qed", but only with "Admitted".
-- The implementation of the admit tactic has changed: no axiom is
-  generated for the admitted sub proof. "admit" is now an alias for
-  "give_up".  Code relying on this specific behavior of "admit"
-  can be made to work by:
-  * Adding an "Axiom" for each admitted subproof.
-  * Adding a single "Axiom proof_admitted : False." and the Ltac definition
-    "Ltac admit := case proof_admitted.".
-- Matching using "lazymatch" was fundamentally modified. It now behaves
-  like "match" (immediate execution of the matching branch) but without
-  the backtracking mechanism in case of failure.
-- New "tryif t then u else v" tactical which executes "u" in case of success
-  of "t" and "v" in case of failure.
-- New conversion tactic "native_compute": evaluates the goal (or an hypothesis)
-  with a call-by-value strategy, using the OCaml native compiler. Useful on
-  very intensive computations.
-- New "cbn" tactic, a well-behaved simpl.
-- Repeated identical calls to omega should now produce identical proof terms.
-- Tactics btauto, a reflexive Boolean tautology solver.
-- Tactic "tauto" was exceptionally able to destruct other connectives
-  than the binary connectives "and", "or", "prod", "sum", "iff". This
-  non-uniform behavior has been fixed (bug #2680) and tauto is
-  slightly weaker (possible source of incompatibilities). On the
-  opposite side, new tactic "dtauto" is able to destruct any
-  record-like inductive types, superseding the old version of "tauto".
-- Similarly, "intuition" has been made more uniform and, where it now
-  fails, "dintuition" can be used (possible source of incompatibilities).
-- New option "Unset Intuition Negation Unfolding" for deactivating automatic
-  unfolding of "not" in intuition.
-- Tactic notations can now be defined locally to a module (use "Local" prefix).
-- Tactic "red" now reduces head beta-iota redexes (potential source of
-  rare incompatibilities).
-- Tactic "hnf" now reduces inner beta-iota redexes
-  (potential source of rare incompatibilities).
-- Tactic "intro H" now reduces beta-iota redexes if these hide a product
-  (potential source of rare incompatibilities).
-- In Ltac matching on patterns of the form "_ pat1 ... patn" now
-  behaves like if matching on "?X pat1 ... patn", i.e. accepting "_"
-  to be instantiated by an applicative term (experimental at this
-  stage, potential source of incompatibilities).
-- In Ltac matching on goal, types of hypotheses are now interpreted in
-  the %type scope (possible source of incompatibilities).
-- "change ... in ..." and "simpl ... in ..." now properly consider nested
-  occurrences (possible source of incompatibilities since this alters
-  the numbering of occurrences), but do not support nested occurrences.
-- Tactics simpl, vm_compute and native_compute can be given a notation string
-  to a constant as argument.
-- When given a reference as argument, simpl, vm_compute and
-  native_compute now strictly interpret it as the head of a pattern
-  starting with this reference.
-- The "change p with c" tactic semantics changed, now type-checking
-  "c" at each matching occurrence "t" of the pattern "p", and
-  converting "t" with "c".
-- Now "appcontext" and "context" behave the same. The old buggy behavior of
-  "context" can be retrieved at parse time by setting the
-  "Tactic Compat Context" flag (possible source of incompatibilities).
-- New introduction pattern p/c which applies lemma c on the fly on the
-  hypothesis under consideration before continuing with introduction pattern p.
-- New introduction pattern [= x1 .. xn] applies "injection as [x1 .. xn]"
-  on the fly if injection is applicable to the hypothesis under consideration
-  (idea borrowed from Georges Gonthier). Introduction pattern [=] applies
-  "discriminate" if a discriminable equality.
-- New introduction patterns * and ** to respectively introduce all forthcoming
-  dependent variables and all variables/hypotheses dependent or not.
-- Tactic "injection c as ipats" now clears c if c refers to an
-  hypothesis and moves the resulting equations in the hypotheses
-  independently of the number of ipats, which has itself to be less
-  than the number of new hypotheses (possible source of incompatibilities;
-  former behavior obtainable by "Unset Injection L2R Pattern Order").
-- Tactic "injection" now automatically simplifies subgoals
-  "existT n p = existT n p'" into "p = p'" when "n" is in an inductive type for
-  which a decidable equality scheme has been generated with "Scheme Equality"
-  (possible source of incompatibilities).
-- New tactic "rewrite_strat" for generalized rewriting with user-defined
-  strategies, subsuming autorewrite.
-- Injection can now also deduce equality of arguments of sort Prop, by using
-  the option "Set Injection On Proofs" (disabled by default). Also improved the
-  error messages.
-- Tactic "subst id" now supports id occurring in dependent local definitions.
-- Bugs fixed about intro-pattern "*" might lead to some rare incompatibilities.
-- New tactical "time" to display time spent executing its argument.
-- Tactics referring or using a constant dependent in a section variable which
-  has been cleared or renamed in the current goal context now fail
-  (possible source of incompatibilities solvable by avoiding clearing
-  the relevant hypotheses).
-- New construct "uconstr:c" and "type_term c" to build untyped terms.
-- Binders in terms defined in Ltac (either "constr" or "uconstr") can
-  now take their names from identifiers defined in Ltac. As a
-  consequence, a name cannot be used in a binder "constr:(fun x =>
-  ...)" if an Ltac variable of that name already exists and does not
-  contain an identifier. Source of occasional incompatibilities.
-- The "refine" tactic now accepts untyped terms built with "uconstr"
-  so that terms with holes can be constructed piecewise in Ltac.
-- New bullets --, ++, **, ---, +++, ***, ... made available.
-- More informative messages when wrong bullet is used.
-- Bullet suggestion when a subgoal is solved.
-- New tactic "enough", symmetric to "assert", but with subgoals
-  swapped, as a more friendly replacement of "cut".
-- In destruct/induction, experimental modifier "!" prefixing the
-  hypothesis name to tell not erasing the hypothesis.
-- Bug fixes in "inversion as" may occasionally lead to incompatibilities.
-- Behavior of introduction patterns -> and <- made more uniform
-  (hypothesis is cleared, rewrite in hypotheses and conclusion and
-  erasing the variable when rewriting a variable).
-- New experimental option "Set Standard Proposition Elimination Names"
-  so that case analysis or induction on schemes in Type containing
-  propositions now produces "H"-based names.
-- Tactics from plugins are now active only when the corresponding module
-  is imported (source of incompatibilities, solvable by adding an "Import";
-  in the particular case of Omega, use "Require Import OmegaTactic").
-- Semantics of destruct/induction has been made more regular in some
-  edge cases, possibly leading to incompatibilities:
-  - new goals are now opened when the term does not match a subterm of
-    the goal and has unresolved holes, while in 8.4 these holes were
-    turned into existential variables
-  - when no "at" option is given, the historical semantics which
-    selects all subterms syntactically identical to the first subterm
-    matching the given pattern is used
-  - non-dependent destruct/induction on an hypothesis with premises in
-    an inductive type with indices is fixed
-  - residual local definitions are now correctly removed.
-- The rename tactic may now replace variables in parallel.
-- A new "Info" command replaces the "info" tactical discontinued in
-  v8.4. It still gives informative results in many cases.
-- The "info_auto" tactic is known to be broken and does not print a
-  trace anymore. Use "Info 1 auto" instead. The same goes for
-  "info_trivial". On the other hand "info_eauto" still works fine,
-  while "Info 1 eauto" prints a trivial trace.
-- When using a lemma of the prototypical form "forall A, {a:A & P a}",
-  "apply" and "apply in" do not instantiate anymore "A" with the
-  current goal and use "a" as the proof, as they were sometimes doing,
-  now considering that it is a too powerful decision.
-
-Program
-
-- "Solve Obligations using" changed to "Solve Obligations with",
-  consistent with "Proof with".
-- Program Lemma, Definition now respect automatic introduction.
-- Program Lemma, Definition, etc.. now interpret "->" like Lemma and
-  Definition as a non-dependent arrow (potential source of
-  incompatibility).
-- Add/document "Set Hide Obligations" (to hide obligations in the final
-  term inside an implicit argument) and "Set Shrink Obligations" (to
-  minimize dependencies of obligations defined by tactics).
-
-Notations
-
-- The syntax "x -> y" is now declared at level 99. In particular, it has
-  now a lower priority than "<->": "A -> B <-> C" is now "A -> (B <-> C)"
-  (possible source of incompatibilities)
-- Notations accept term-providing tactics using the $(...)$ syntax.
-- "Bind Scope" can no longer bind "Funclass" and "Sortclass".
-- A notation can be given a (compat "8.x") annotation, making it behave
-  like a "only parsing" notation, but the annotation may lead to eventually
-  issue warnings or errors in further versions when this notation is used.
-- More systematic insertion of spaces as a default for printing
-  notations ("format" still available to override the default).
-- In notations, a level modifier referring to a non-existent variable is
-  now considered an error rather than silently ignored.
-
-Tools
-
-- Option -I now only adds directories to the ml path.
-- Option -Q behaves as -R, except that the logical path of any loaded file has
-  to be fully qualified.
-- Option -R no longer adds recursively to the ml path; only the root
-  directory is added. (Behavior with respect to the load path is
-  unchanged.)
-- Option -nois prevents coq/theories and coq/plugins to be recursively
-  added to the load path. (Same behavior as with coq/user-contrib.)
-- coqdep accepts a -dumpgraph option generating a dot file.
-- Makefiles generated through coq_makefile have three new targets "quick"
-  "checkproofs" and "vio2vo", allowing respectively to asynchronously compile
-  the files without playing the proof scripts, asynchronously checking
-  that the quickly generated proofs are correct and generating the object
-  files from the quickly generated proofs.
-- The XML plugin was discontinued and removed from the source.
-- A new utility called coqworkmgr can be used to limit the number of
-  concurrent workers started by independent processes, like make and CoqIDE.
-  This is of interest for users of the par: goal selector.
-
-Interfaces
-
-- CoqIDE supports asynchronous edition of the document, ongoing tasks and
-  errors are reported in the bottom right window.  The number of workers
-  taking care of processing proofs can be selected with -async-proofs-j.
-- CoqIDE highlights in yellow "unsafe" commands such as axiom
-  declarations, and tactics like "give_up".
-- CoqIDE supports Proof General like key bindings;
-  to activate the PG mode go to Edit -> Preferences -> Editor.
-  For the documentation see Help -> Help for PG mode.
-- CoqIDE automatically retracts the locked area when one edits the
-  locked text.
-- CoqIDE search and replace got regular expressions power. See the
-  documentation of OCaml's Str module for the supported syntax.
-- Many CoqIDE windows, including the query one, are now detachable to
-  improve usability on multi screen work stations.
-- Coqtop/coqc outputs highlighted syntax. Colors can be configured thanks
-  to the COQ_COLORS environment variable, and their current state can
-  be displayed with the -list-tags command line option.
-- Third party user interfaces can install their main loop in $COQLIB/toploop
-  and call coqtop with the -toploop flag to select it.
-
-Internal Infrastructure
-
-- Many reorganizations in the ocaml source files. For instance,
-  many internal a.s.t. of Coq are now placed in mli files in
-  a new directory intf/, for instance constrexpr.mli or glob_term.mli.
-  More details in dev/doc/changes.
-- The file states/initial.coq does not exist anymore. Instead, coqtop
-  initially does a "Require" of Prelude.vo (or nothing when given
-  the options -noinit or -nois).
-- The format of vo files has slightly changed: cf final comments in
-  checker/cic.mli.
-- The build system does not produce anymore programs named coqtop.opt
-  and a symbolic link to coqtop. Instead, coqtop is now directly
-  an executable compiled with the best OCaml compiler available.
-  The bytecode program coqtop.byte is still produced. Same for other
-  utilities.
-- Some options of the ./configure script slightly changed:
-  * The -coqrunbyteflags and its blank-separated argument is replaced
-    by option -vmbyteflags which expects a comma-separated argument.
-  * The -coqtoolsbyteflags option is discontinued, see -no-custom instead.
-
-Miscellaneous
-
-- ML plugins now require a "DECLARE PLUGIN \"foo\"" statement. The "foo" name
-  must be exactly the name of the ML module that will be loaded through a
-  "Declare ML \"foo\"" command.
-
-Changes from V8.4beta2 to V8.4
-==============================
-
-Vernacular commands
-
-- The "Reset" command is now supported again in files given to coqc or Load.
-- "Show Script" now indents again the displayed scripts. It can also work
-  correctly across Load'ed files if the option "Unset Atomic Load" is used.
-- "Open Scope" can now be given the delimiter (e.g. Z) instead of the full
-  scope name (e.g. Z_scope).
-
-Notations
-
-- Most compatibility notations of the standard library are now tagged as
-  (compat xyz), where xyz is a former Coq version, for instance "8.3".
-  These notations behave as (only parsing) notations, except that they may
-  triggers warnings (or errors) when used while Coq is not in a corresponding
-  -compat mode.
-- To activate these compatibility warnings, use "Set Verbose Compat Notations"
-  or the command-line flag -verbose-compat-notations.
-- For a strict mode without these compatibility notations, use
-  "Unset Compat Notations" or the command-line flag -no-compat-notations.
-
-Tactics
-
-- An annotation "eqn:H" or "eqn:?" can be added to a "destruct"
-  or "induction" to make it generate equations in the spirit of "case_eq".
-  The former syntax "_eqn" is discontinued.
-- The name of the hypothesis introduced by tactic "remember" can be
-  set via the new syntax "remember t as x eqn:H" (wish #2489).
-
-Libraries
-
-- Reals: changed definition of PI, no more axiom about sin(PI/2).
-- SetoidPermutation: a notion of permutation for lists modulo a setoid equality.
-- BigN: fixed the ocaml code doing the parsing/printing of big numbers.
-- List: a couple of lemmas added especially about no-duplication, partitions.
-- Init: Removal of the coercions between variants of sigma-types and
-  subset types (possible source of incompatibility).
-
-Changes from V8.4beta to V8.4beta2
-==================================
-
-Vernacular commands
-
-- Commands "Back" and "BackTo" are now handling the proof states. They may
-  perform some extra steps of backtrack to avoid states where the proof
-  state is unavailable (typically a closed proof).
-- The commands "Suspend" and "Resume" have been removed.
-- A basic Show Script has been reintroduced (no indentation).
-- New command "Set Parsing Explicit" for deactivating parsing (and printing)
-  of implicit arguments (useful for teaching).
-- New command "Grab Existential Variables" to transform the unresolved evars
-  at the end of a proof into goals.
-
-Tactics
-
-- Still no general "info" tactical, but new specific tactics info_auto,
-  info_eauto, info_trivial which provides information on the proofs found
-  by auto/eauto/trivial. Display of these details could also be activated by
-  "Set Info Auto"/"Set Info Eauto"/"Set Info Trivial".
-- Details on everything tried by auto/eauto/trivial during a proof search
-  could be obtained by "debug auto", "debug eauto", "debug trivial" or by a
-  global "Set Debug Auto"/"Set Debug Eauto"/"Set Debug Trivial".
-- New command "r string" in Ltac debugger that interprets "idtac
-  string" in Ltac code as a breakpoint and jumps to its next use.
-- Tactics from the Dp plugin (simplify, ergo, yices, cvc3, z3, cvcl,
-  harvey, zenon, gwhy) have been removed, since Why2 has not been
-  maintained for the last few years. The Why3 plugin should be a suitable
-  replacement in most cases.
-
-Libraries
-
-- MSetRBT: a new implementation of MSets via Red-Black trees (initial
-  contribution by Andrew Appel).
-- MSetAVL: for maximal sharing with the new MSetRBT, the argument order
-  of Node has changed (this should be transparent to regular MSets users).
-
-Module System
-
-- The names of modules (and module types) are now in a fully separated
-  namespace from ordinary definitions: "Definition E:=0. Module E. End E."
-  is now accepted.
-
-CoqIDE
-
-- Coqide now supports the "Restart" command, and "Undo" (with a warning).
-  Better support for "Abort".
-
-Changes from V8.3 to V8.4beta
-=============================
-
-Logic
-
-- Standard eta-conversion now supported (dependent product only).
-- Guard condition improvement: subterm property is propagated through beta-redex
-  blocked by pattern-matching, as in "(match v with C .. => fun x => u end) x";
-  this allows for instance to use "rewrite ... in ..." without breaking
-  the guard condition.
-
-Specification language and notations
-
-- Maximal implicit arguments can now be set locally by { }. The registration
-  traverses fixpoints and lambdas. Because there is conversion in types,
-  maximal implicit arguments are not taken into account in partial
-  applications (use eta expanded form with explicit { } instead).
-- Added support for recursive notations with binders (allows for instance
-  to write "exists x y z, P").
-- Structure/Record printing can be disable by "Unset Printing Records".
-  In addition, it can be controlled on type by type basis using
-  "Add Printing Record" or "Add Printing Constructor".
-- Pattern-matching compilation algorithm: in "match x, y with ... end",
-  possible dependencies of x (or of the indices of its type) in the type
-  of y are now taken into account.
-
-Tactics
-
-- New proof engine.
-- Scripts can now be structured thanks to bullets - * + and to subgoal
-  delimitation via { }. Note: for use with Proof General, a cvs version of
-  Proof General no older than mid-July 2011 is currently required.
-- Support for tactical "info" is suspended.
-- Support for command "Show Script" is suspended.
-- New tactics constr_eq, is_evar and has_evar for use in Ltac (DOC TODO).
-- Removed the two-argument variant of "decide equality".
-- New experimental tactical "timeout <n> <tac>". Since <n> is a time
-  in second for the moment, this feature should rather be avoided
-  in scripts meant to be machine-independent.
-- Fix in "destruct": removal of unexpected local definitions in context might
-  result in some rare incompatibilities (solvable by adapting name hypotheses).
-- Introduction pattern "_" made more robust.
-- Tactic (and Eval command) vm_compute can now be interrupted via Ctrl-C.
-- Unification in "apply" supports unification of patterns of the form
-  ?f x y = g(x,y) (compatibility ensured by using
-  "Unset Tactic Pattern Unification"). It also supports (full) betaiota.
-- Tactic autorewrite does no longer instantiate pre-existing
-  existential variables (theoretical source of possible incompatibilities).
-- Tactic "dependent rewrite" now supports equality in "sig".
-- Tactic omega now understands Zpred (wish #1912) and can prove any goal
-  from a context containing an arithmetical contradiction (wish #2236).
-- Using "auto with nocore" disables the use of the "core" database (wish #2188).
-  This pseudo-database "nocore" can also be used with trivial and eauto.
-- Tactics "set", "destruct" and "induction" accepts incomplete terms and
-  use the goal to complete the pattern assuming it is non ambiguous.
-- When used on arguments with a dependent type, tactics such as
-  "destruct", "induction", "case", "elim", etc. now try to abstract
-  automatically the dependencies over the arguments of the types
-  (based on initial ideas from Chung-Kil Hur, extension to nested
-   dependencies suggested by Dan Grayson)
-- Tactic "injection" now failing on an equality showing no constructors while
-  it was formerly generalizing again the goal over the given equality.
-- In Ltac, the "context [...]" syntax has now a variant "appcontext [...]"
-  allowing to match partial applications in larger applications.
-- When applying destruct or inversion on a fixpoint hiding an inductive
-  type, recursive calls to the fixpoint now remain folded by default (rare
-  source of incompatibility generally solvable by adding a call to simpl).
-- In an ltac pattern containing a "match", a final "| _ => _" branch could be
-  used now instead of enumerating all remaining constructors. Moreover, the
-  pattern "match _ with _ => _ end" now allows to match any "match". A "in"
-  annotation can also be added to restrict to a precise inductive type.
-- The behavior of "simpl" can be tuned using the "Arguments" vernacular.
-  In particular constants can be marked so that they are always/never unfolded
-  by "simpl", or unfolded only when a set of arguments evaluates to a
-  constructor. Last one can mark a constant so that it is unfolded only if the
-  simplified term does not expose a match in head position.
-
-Vernacular commands
-
-- It is now mandatory to have a space (or tabulation or newline or end-of-file)
-  after a "." ending a sentence.
-- In SearchAbout, the [ ] delimiters are now optional.
-- New command "Add/Remove Search Blacklist <substring> ...":
-  a Search or SearchAbout or similar query will never mention lemmas
-  whose qualified names contain any of the declared substrings.
-  The default blacklisted substrings are "_subproof" "Private_".
-- When the output file of "Print Universes" ends in ".dot" or ".gv",
-  the universe graph is printed in the DOT language, and can be
-  processed by Graphviz tools.
-- New command "Print Sorted Universes".
-- The undocumented and obsolete option "Set/Unset Boxed Definitions" has
-  been removed, as well as syntaxes like "Boxed Fixpoint foo".
-- A new option "Set Default Timeout n / Unset Default Timeout".
-- Qed now uses information from the reduction tactics used in proof script
-  to avoid conversion at Qed time to go into a very long computation.
-- New command "Show Goal ident" to display the statement of a goal, even
-  a closed one (available from Proof General).
-- Command "Proof" accept a new modifier "using" to force generalization
-  over a given list of section variables at section ending (DOC TODO).
-- New command "Arguments" generalizing "Implicit Arguments" and
-  "Arguments Scope" and that also allows to rename the parameters of a
-  definition and to tune the behavior of the tactic "simpl".
-
-Module System
-
-- During subtyping checks, an opaque constant in a module type could now
-  be implemented by anything of the right type, even if bodies differ.
-  Said otherwise, with respect to subtyping, an opaque constant behaves
-  just as a parameter. Coqchk was already implementing this, but not coqtop.
-- The inlining done during application of functors can now be controlled
-  more precisely, by the annotations (no inline) or (inline at level XX).
-  With the latter annotation, only functor parameters whose levels
-  are lower or equal than XX will be inlined.
-  The level of a parameter can be fixed by "Parameter Inline(30) foo".
-  When levels aren't given, the default value is 100. One can also use
-  the flag "Set Inline Level ..." to set a level (DOC TODO).
-- Print Assumptions should now handle correctly opaque modules (#2168).
-- Print Module (Type) now tries to print more details, such as types and
-  bodies of the module elements. Note that Print Module Type could be
-  used on a module to display only its interface. The option
-  "Set Short Module Printing" could be used to switch back to the earlier
-  behavior were only field names were displayed.
-
-Libraries
-
-- Extension of the abstract part of Numbers, which now provide axiomatizations
-  and results about many more integer functions, such as pow, gcd, lcm, sqrt,
-  log2 and bitwise functions. These functions are implemented for nat, N, BigN,
-  Z, BigZ. See in particular file NPeano for new functions about nat.
-- The definition of types positive, N, Z is now in file BinNums.v
-- Major reorganization of ZArith. The initial file ZArith/BinInt.v now contains
-  an internal module Z implementing the Numbers interface for integers.
-  This module Z regroups:
-  * all functions over type Z : Z.add, Z.mul, ...
-  * the minimal proofs of specifications for these functions : Z.add_0_l, ...
-  * an instantation of all derived properties proved generically in Numbers :
-    Z.add_comm, Z.add_assoc, ...
-  A large part of ZArith is now simply compatibility notations, for instance
-  Zplus_comm is an alias for Z.add_comm. The direct use of module Z is now
-  recommended instead of relying on these compatibility notations.
-- Similar major reorganization of NArith, via a module N in NArith/BinNat.v
-- Concerning the positive datatype, BinPos.v is now in a specific directory
-  PArith, and contains an internal submodule Pos. We regroup there functions
-  such as Pos.add Pos.mul etc as well as many results about them. These results
-  are here proved directly (no Number interface for strictly positive numbers).
-- Note that in spite of the compatibility layers, all these reorganizations
-  may induce some marginal incompatibilies in scripts. In particular:
-  * the "?=" notation for positive now refers to a binary function Pos.compare,
-    instead of the infamous ternary Pcompare (now Pos.compare_cont).
-  * some hypothesis names generated by the system may changed (typically for
-    a "destruct Z_le_gt_dec") since naming is done after the short name of
-    the head predicate (here now "le" in module Z instead of "Zle", etc).
-  * the internals of Z.add has changed, now relying of Z.pos_sub.
-- Also note these new notations:
-  * "<?" "<=?" "=?" for boolean tests such as Z.ltb Z.leb Z.eqb.
-  * "÷" for the alternative integer division Z.quot implementing the Truncate
-    convention (former ZOdiv), while the notation for the Coq usual division
-    Z.div implementing the Flooring convention remains "/". Their corresponding
-    modulo functions are Z.rem (no notations) for Z.quot and Z.modulo (infix
-    "mod" notation) for Z.div.
-- Lemmas about conversions between these datatypes are also organized
-  in modules, see for instance modules Z2Nat, N2Z, etc.
-- When creating BigN, the macro-generated part NMake_gen is much smaller.
-  The generic part NMake has been reworked and improved. Some changes
-  may introduce incompatibilities. In particular, the order of the arguments
-  for BigN.shiftl and BigN.shiftr is now reversed: the number to shift now
-  comes first. By default, the power function now takes two BigN.
-- Creation of Vector, an independent library for lists indexed by their length.
-  Vectors' names overwrite lists' one so you should not "Import" the library.
-  All old names changed: function names follow the ocaml ones and, for example,
-  Vcons becomes Vector.cons. You can get [..;..;..]-style notations by importing
-  Vector.VectorNotations.
-- Removal of TheoryList. Requiring List instead should work most of the time.
-- New syntax "rew Heq in H" and "rew <- Heq in H" for eq_rect and
-  eq_rect_r (available by importing module EqNotations).
-- Wf.iter_nat is now Peano.nat_iter (with an implicit type argument).
-
-Internal infrastructure
-
-- Opaque proofs are now loaded lazily by default. This allows to be almost as
-  fast as -dont-load-proofs, while being safer (no creation of axioms) and
-  avoiding feature restrictions (Print and Print Assumptions work ok).
-- Revised hash-consing code allowing more sharing of memory
-- Experimental support added for camlp4 (the one provided alongside ocaml),
-  simply pass option -usecamlp4 to ./configure. By default camlp5 is used.
-- Revised build system: no more stages in Makefile thanks to some recursive
-  aspect of recent gnu make, use of vo.itarget files containing .v to compile
-  for both make and ocamlbuild, etc.
-- Support of cross-compilation via mingw from unix toward Windows,
-  contact P. Letouzey for more informations.
-- New Makefile rules mli-doc to make html of mli in dev/doc/html and
-  full-stdlib to get a (huge) pdf reflecting the whole standard library.
-
-Extraction
-
-- By default, opaque terms are now truly considered opaque by extraction:
-  instead of accessing their body, they are now considered as axioms.
-  The previous behaviour can be reactivated via the option
-  "Set Extraction AccessOpaque".
-- The pretty-printer for Haskell now produces layout-independent code
-- A new command "Separate Extraction cst1 cst2 ..." that mixes a
-  minimal extracted environment a la "Recursive Extraction" and the
-  production of several files (one per coq source) a la "Extraction Library"
-  (DOC TODO).
-- New option "Set/Unset Extraction KeepSingleton" for preventing the
-  extraction to optimize singleton container types (DOC TODO).
-- The extraction now identifies and properly rejects a particular case of
-  universe polymorphism it cannot handle yet (the pair (I,I) being Prop).
-- Support of anonymous fields in record (#2555).
-
-CoqIDE
-
-- Coqide now runs coqtop as separated process, making it more robust:
-  coqtop subprocess can be interrupted, or even killed and relaunched
-  (cf button "Restart Coq", ex-"Go to Start"). For allowing such
-  interrupts, the Windows version of coqide now requires Windows >= XP
-  SP1.
-- The communication between CoqIDE and Coqtop is now done via a dialect
-  of XML (DOC TODO).
-- The backtrack engine of CoqIDE has been reworked, it now uses the
-  "Backtrack" command similarly to Proof General.
-- The Coqide parsing of sentences has be reworked and now supports
-  tactic delimitation via { }.
-- Coqide now accepts the Abort command (wish #2357).
-- Coqide can read coq_makefile files as "project file" and use it to
-  set automatically options to send to coqtop.
-- Preference files have moved to $XDG_CONFIG_HOME/coq and accelerators
-  are not stored as a list anymore.
-
-Tools
-
-- Coq now searches directories specified in COQPATH, $XDG_DATA_HOME/coq,
-  $XDG_DATA_DIRS/coq, and user-contribs before the standard library.
-- Coq rc file has moved to $XDG_CONFIG_HOME/coq.
-- Major changes to coq_makefile:
-  * mli/mlpack/mllib taken into account, ml not preproccessed anymore, ml4 work;
-  * mlihtml generates doc of mli, install-doc install the html doc in DOCDIR
-    with the same policy as vo in COQLIB;
-  * More variables are given by coqtop -config, others are defined only if the
-    users doesn't have defined them elsewhere. Consequently, generated makefile
-    should work directly on any architecture;
-  * Packagers can take advantage of $(DSTROOT) introduction. Installation can
-    be made in $XDG_DATA_HOME/coq;
-  * -arg option allows to send option as argument to coqc.
-
-Changes from V8.2 to V8.3
-=========================
-
-Rewriting tactics
-
-- Tactic "rewrite" now supports rewriting on ad hoc equalities such as eq_true.
-- "Hint Rewrite" now checks that the lemma looks like an equation.
-- New tactic "etransitivity".
-- Support for heterogeneous equality (JMeq) in "injection" and "discriminate".
-- Tactic "subst" now supports heterogeneous equality and equality
-  proofs that are dependent (use "simple subst" for preserving compatibility).
-- Added support for Leibniz-rewriting of dependent hypotheses.
-- Renamed "Morphism" into "Proper" and "respect" into "proper_prf"
-  (possible source of incompatibility). A partial fix is to define
-  "Notation Morphism R f := (Proper (R%signature) f)."
-- New tactic variants "rewrite* by" and "autorewrite*" that rewrite
-  respectively the first and all matches whose side-conditions are
-  solved.
-- "Require Import Setoid" does not export all of "Morphisms" and
-  "RelationClasses" anymore (possible source of incompatibility, fixed
-  by importing "Morphisms" too).
-- Support added for using Chung-Kil Hur's Heq library for rewriting over
-  heterogeneous equality (courtesy of the library's author).
-- Tactic "replace" supports matching terms with holes.
-
-Automation tactics
-
-- Tactic "intuition" now preserves inner "iff" and "not" (exceptional
-  source of incompatibilities solvable by redefining "intuition" as
-  "unfold iff, not in *; intuition", or, for iff only, by using
-  "Set Intuition Iff Unfolding".)
-- Tactic "tauto" now proves classical tautologies as soon as classical logic
-  (i.e. library Classical_Prop or Classical) is loaded.
-- Tactic "gappa" has been removed from the Dp plugin.
-- Tactic "firstorder" now supports the combination of its "using" and
-  "with" options.
-- New "Hint Resolve ->" (or "<-") for declaring iff's as oriented
-  hints (wish #2104).
-- An inductive type as argument of the "using" option of "auto/eauto/firstorder"
-  is interpreted as using the collection of its constructors.
-- New decision tactic "nsatz" to prove polynomial equations
-  by computation of Groebner bases.
-
-Other tactics
-
-- Tactic "discriminate" now performs intros before trying to discriminate an
-  hypothesis of the goal (previously it applied intro only if the goal
-  had the form t1<>t2) (exceptional source of incompatibilities - former
-  behavior can be obtained by "Unset Discriminate Introduction").
-- Tactic "quote" now supports quotation of arbitrary terms (not just the
-  goal).
-- Tactic "idtac" now displays its "list" arguments.
-- New introduction patterns "*" for introducing the next block of dependent
-  variables and "**" for introducing all quantified variables and hypotheses.
-- Pattern Unification for existential variables activated in tactics and
-  new option "Unset Tactic Evars Pattern Unification" to deactivate it.
-- Resolution of canonical structure is now part of the tactic's unification
-  algorithm.
-- New tactic "decide lemma with hyp" for rewriting decidability lemmas
-  when one knows which side is true.
-- Improved support of dependent goals over objects in dependent types for
-  "destruct" (rare source of incompatibility that can be avoided by unsetting
-  option "Dependent Propositions Elimination").
-- Tactic "exists", "eexists", "destruct" and "edestruct" supports iteration
-  using comma-separated arguments.
-- Tactic names "case" and "elim" now support clauses "as" and "in" and become
-  then synonymous of "destruct" and "induction" respectively.
-- A new tactic name "exfalso" for the use of 'ex-falso quodlibet' principle.
-  This tactic is simply a shortcut for "elimtype False".
-- Made quantified hypotheses get the name they would have if introduced in
-  the context (possible but rare source of incompatibilities).
-- When applying a component of a conjunctive lemma, "apply in" (and
-  sequences of "apply in") now leave the side conditions of the lemmas
-  uniformly after the main goal (possible source of rare incompatibilities).
-- In "simpl c" and "change c with d", c can be a pattern.
-- Tactic "revert" now preserves let-in's making it the exact inverse of
-  "intro".
-- New tactics "clear dependent H" and "revert dependent H" that
-  clears (resp. reverts) H and all the hypotheses that depend on H.
-- Ltac's pattern-matching now supports matching metavariables that
-  depend on variables bound upwards in the pattern.
-
-Tactic definitions
-
-- Ltac definitions support Local option for non-export outside modules.
-- Support for parsing non-empty lists with separators in tactic notations.
-- New command "Locate Ltac" to get the full name of an Ltac definition.
-
-Notations
-
-- Record syntax "{|x=...; y=...|}" now works inside patterns too.
-- Abbreviations from non-imported module now invisible at printing time.
-- Abbreviations now use implicit arguments and arguments scopes for printing.
-- Abbreviations to pure names now strictly behave like the name they refer to
-  (make redirections of qualified names easier).
-- Abbreviations for applied constant now propagate the implicit arguments
-  and arguments scope of the underlying reference (possible source of
-  incompatibilities generally solvable by changing such abbreviations from
-  e.g. "Notation foo' := (foo x)" to "Notation foo' y := (foo x (y:=y))").
-- The "where" clause now supports multiple notations per defined object.
-- Recursive notations automatically expand one step on the left for better
-  factorization; recursion notations inner separators now ensured being tokens.
-- Added "Reserved Infix" as a specific shortcut of the corresponding
-  "Reserved Notation".
-- Open/Close Scope command supports Global option in sections.
-
-Specification language
-
-- New support for local binders in the syntax of Record/Structure fields.
-- Fixpoint/CoFixpoint now support building part or all of bodies using tactics.
-- Binders given before ":" in lemmas and in definitions built by tactics are
-  now automatically introduced (possible source of incompatibility that can
-  be resolved by invoking "Unset Automatic Introduction").
-- New support for multiple implicit arguments signatures per reference.
-
-Module system
-
-- Include Type is now deprecated since Include now accept both modules and
-  module types.
-- Declare ML Module supports Local option.
-- The sharing between non-logical object and the management of the
-  name-space has been improved by the new "Delta-equivalence" on
-  qualified name.
-- The include operator has been extended to high-order structures
-- Sequences of Include can be abbreviated via new syntax "<+".
-- A module (or module type) can be given several "<:" signatures.
-- Interactive proofs are now permitted in module type. Functors can hence
-  be declared as Module Type and be used later to type themselves.
-- A functor application can be prefixed by a "!" to make it ignore any
-  "Inline" annotation in the type of its argument(s) (for examples of
-  use of the new features, see libraries Structures and Numbers).
-- Coercions are now active only when modules are imported (use "Set Automatic
-  Coercions Import" to get the behavior of the previous versions of Coq).
-
-Extraction
-
-- When using (Recursive) Extraction Library, the filenames are directly the
-  Coq ones with new appropriate extensions : we do not force anymore
-  uncapital first letters for Ocaml and capital ones for Haskell.
-- The extraction now tries harder to avoid code transformations that can be
-  dangerous for the complexity. In particular many eta-expansions at the top
-  of functions body are now avoided, clever partial applications will likely
-  be preserved, let-ins are almost always kept, etc.
-- In the same spirit, auto-inlining is now disabled by default, except for
-  induction principles, since this feature was producing more frequently
-  weird code than clear gain. The previous behavior can be restored via
-  "Set Extraction AutoInline".
-- Unicode characters in identifiers are now transformed into ascii strings
-  that are legal in Ocaml and other languages.
-- Harsh support of module extraction to Haskell and Scheme: module hierarchy
-  is flattened, module abbreviations and functor applications are expanded,
-  module types and unapplied functors are discarded.
-- Less unsupported situations when extracting modules to Ocaml. In particular
-  module parameters might be alpha-renamed if a name clash is detected.
-- Extract Inductive is now possible toward non-inductive types (e.g. nat => int)
-- Extraction Implicit: this new experimental command allows to mark
-  some arguments of a function or constructor for removed during
-  extraction, even if these arguments don't fit the usual elimination
-  principles of extraction, for instance the length n of a vector.
-- Files ExtrOcaml*.v in plugins/extraction try to provide a library of common
-  extraction commands: mapping of basics types toward Ocaml's counterparts,
-  conversions from/to int and big_int, or even complete mapping of nat,Z,N
-  to int or big_int, or mapping of ascii to char and string to char list
-  (in this case recognition of ascii constants is hard-wired in the extraction).
-
-Program
-
-- Streamlined definitions using well-founded recursion and measures so
-  that they can work on any subset of the arguments directly (uses currying).
-- Try to automatically clear structural fixpoint prototypes in
-  obligations to avoid issues with opacity.
-- Use return type clause inference in pattern-matching as in the standard
-  typing algorithm.
-- Support [Local Obligation Tactic] and [Next Obligation with tactic].
-- Use [Show Obligation Tactic] to print the current default tactic.
-- [fst] and [snd] have maximal implicit arguments in Program now (possible
-  source of incompatibility).
-
-Type classes
-
-- Declaring axiomatic type class instances in Module Type should be now
-  done via new command "Declare Instance", while the syntax "Instance"
-  now always provides a concrete instance, both in and out of Module Type.
-- Use [Existing Class foo] to declare foo as a class a posteriori.
-  [foo] can be an inductive type or a constant definition. No
-  projections or instances are defined.
-- Various bug fixes and improvements: support for defined fields,
-  anonymous instances, declarations giving terms, better handling of
-  sections and [Context].
-
-Vernacular commands
-
-- New command "Timeout <n> <command>." interprets a command and a timeout
-  interrupts the interpretation after <n> seconds.
-- New command "Compute <expr>." is a shortcut for "Eval vm_compute in <expr>".
-- New command "Fail <command>." interprets a command and is successful iff
-  the command fails on an error (but not an anomaly). Handy for tests and
-  illustration of wrong commands.
-- Most commands referring to constant (e.g. Print or About) now support
-  referring to the constant by a notation string.
-- New option "Boolean Equality Schemes" to make generation of boolean
-  equality automatic for datatypes (together with option "Decidable
-  Equality Schemes", this replaces deprecated option "Equality Scheme").
-- Made support for automatic generation of case analysis schemes available
-  to user (governed by option "Set Case Analysis Schemes").
-- New command "(Global?) Generalizable [All|No] Variable(s)? ident(s)?" to
-  declare which identifiers are generalizable in `{} and `() binders.
-- New command "Print Opaque Dependencies" to display opaque constants in
-  addition to all variables, parameters or axioms a theorem or
-  definition relies on.
-- New command "Declare Reduction <id> := <conv_expr>", allowing to write
-  later "Eval <id> in ...". This command accepts a Local variant.
-- Syntax of Implicit Type now supports more than one block of variables of
-  a given type.
-- Command "Canonical Structure" now warns when it has no effects.
-- Commands of the form "Set X" or "Unset X" now support "Local" and "Global"
-  prefixes.
-
-Library
-
-- Use "standard" Coq names for the properties of eq and identity
-  (e.g. refl_equal is now eq_refl). Support for compatibility is provided.
-- The function Compare_dec.nat_compare is now defined directly,
-  instead of relying on lt_eq_lt_dec. The earlier version is still
-  available under the name nat_compare_alt.
-- Lemmas in library Relations and Reals have been homogenized a bit.
-- The implicit argument of Logic.eq is now maximally inserted, allowing
-  to simply write "eq" instead of "@eq _" in morphism signatures.
-- Wrongly named lemmas (Zlt_gt_succ and Zlt_succ_gt) fixed (potential source
-  of incompatibilities)
-- List library:
-  - Definitions of list, length and app are now in Init/Datatypes.
-    Support for compatibility is provided.
-  - Definition of Permutation is now in Sorting/Permtation.v
-  - Some other light revisions and extensions (possible source
-    of incompatibilities solvable by qualifying names accordingly).
-- In ListSet, set_map has been fixed (source of incompatibilities if used).
-- Sorting library:
-  - new mergesort of worst-case complexity O(n*ln(n)) made available in
-    Mergesort.v;
-  - former notion of permutation up to setoid from Permutation.v is
-    deprecated and moved to PermutSetoid.v;
-  - heapsort from Heap.v of worst-case complexity O(n*n) is deprecated;
-  - new file Sorted.v for some definitions of being sorted.
-- Structure library. This new library is meant to contain generic
-  structures such as types with equalities or orders, either
-  in Module version (for now) or Type Classes (still to do):
-  - DecidableType.v and OrderedType.v: initial notions for FSets/FMaps,
-    left for compatibility but considered as deprecated.
-  - Equalities.v and Orders.v: evolutions of the previous files,
-    with fine-grain Module architecture, many variants, use of
-    Equivalence and other relevant Type Classes notions.
-  - OrdersTac.v: a generic tactic for solving chains of (in)equalities
-    over variables. See {Nat,N,Z,P}OrderedType.v for concrete instances.
-  - GenericMinMax.v: any ordered type can be equipped with min and max.
-    We derived here all the generic properties of these functions.
-- MSets library: an important evolution of the FSets library.
-  "MSets" stands for Modular (Finite) Sets, by contrast with a forthcoming
-  library of Class (Finite) Sets contributed by S. Lescuyer which will be
-  integrated with the next release of Coq. The main features of MSets are:
-  - The use of Equivalence, Proper and other Type Classes features
-    easing the handling of setoid equalities.
-  - The interfaces are now stated in iff-style. Old specifications
-    are now derived properties.
-  - The compare functions are now pure, and return a "comparison" value.
-    Thanks to the CompSpec inductive type, reasoning on them remains easy.
-  - Sets structures requiring invariants (i.e. sorted lists) are
-    built first as "Raw" sets (pure objects and separate proofs) and
-    attached with their proofs thanks to a generic functor. "Raw" sets
-    have now a proper interface and can be manipulated directly.
-  Note: No Maps yet in MSets. The FSets library is still provided
-  for compatibility, but will probably be considered as deprecated in the
-  next release of Coq.
-- Numbers library:
-  - The abstract layer (NatInt, Natural/Abstract, Integer/Abstract) has
-    been simplified and enhance thanks to new features of the module
-    system such as Include (see above). It has been extended to Euclidean
-    division (three flavors for integers: Trunc, Floor and Math).
-  - The arbitrary-large efficient numbers (BigN, BigZ, BigQ) has also
-    been reworked. They benefit from the abstract layer improvements
-    (especially for div and mod). Note that some specifications have
-    slightly changed (compare, div, mod, shift{r,l}). Ring/Field should
-    work better (true recognition of constants).
-
-Tools
-
-- Option -R now supports binding Coq root read-only.
-- New coqtop/coqc option -beautify to reformat .v files (usable
-  e.g. to globally update notations).
-- New tool beautify-archive to beautify a full archive of developments.
-- New coqtop/coqc option -compat X.Y to simulate the general behavior
-  of previous versions of Coq (provides e.g. support for 8.2 compatibility).
-
-Coqdoc
-
-- List have been revamped.  List depth and scope is now determined by
-  an "offside" whitespace rule.
-- Text may be italicized by placing it in _underscores_.
-- The "--index <string>" flag changes the filename of the index.
-- The "--toc-depth <int>" flag limits the depth of headers which are
-  included in the table of contents.
-- The "--lib-name <string>" flag prints "<string> Foo" instead of
-  "Library Foo" where library titles are called for.  The
-  "--no-lib-name" flag eliminates the extra title.
-- New option "--parse-comments" to allow parsing of regular "(* *)"
-  comments.
-- New option "--plain-comments" to disable interpretation inside comments.
-- New option "--interpolate" to try and typeset identifiers in Coq escapings
-  using the available globalization information.
-- New option "--external url root" to refer to external libraries.
-- Links to section variables and notations now supported.
-
-Internal infrastructure
-
-- To avoid confusion with the repository of user's contributions,
-  the subdirectory "contrib" has been renamed into "plugins".
-  On platforms supporting ocaml native dynlink, code located there
-  is built as loadable plugins for coqtop.
-- An experimental build mechanism via ocamlbuild is provided.
-  From the top of the archive, run ./configure as usual, and
-  then ./build. Feedback about this build mechanism is most welcome.
-  Compiling Coq on platforms such as Windows might be simpler
-  this way, but this remains to be tested.
-- The Makefile system has been simplified and factorized with
-  the ocamlbuild system. In particular "make" takes advantage
-  of .mllib files for building .cma/.cmxa. The .vo files to
-  compile are now listed in several vo.itarget files.
-
-Changes from V8.1 to V8.2
-=========================
-
-Language
-
-- If a fixpoint is not written with an explicit { struct ... }, then
-  all arguments are tried successively (from left to right) until one is
-  found that satisfies the structural decreasing condition.
-- New experimental typeclass system giving ad-hoc polymorphism and
-  overloading based on dependent records and implicit arguments.
-- New syntax "let 'pat := b in c" for let-binding using irrefutable patterns.
-- New syntax "forall {A}, T" for specifying maximally inserted implicit
-  arguments in terms.
-- Sort of Record/Structure, Inductive and CoInductive defaults to Type
-  if omitted.
-- (Co)Inductive types can be defined as records
-  (e.g. "CoInductive stream := { hd : nat; tl : stream }.")
-- New syntax "Theorem id1:t1 ... with idn:tn" for proving mutually dependent
-  statements.
-- Support for sort-polymorphism on constants denoting inductive types.
-- Several evolutions of the module system (handling of module aliases,
-  functorial module types, an Include feature, etc).
-- Prop now a subtype of Set (predicative and impredicative forms).
-- Recursive inductive types in Prop with a single constructor of which
-  all arguments are in Prop is now considered to be a singleton
-  type. It consequently supports all eliminations to Prop, Set and Type.
-  As a consequence, Acc_rect has now a more direct proof [possible source
-  of easily fixed incompatibility in case of manual definition of a recursor
-  in a recursive singleton inductive type].
-
-Vernacular commands
-
-- Added option Global to "Arguments Scope" for section surviving.
-- Added option "Unset Elimination Schemes" to deactivate the automatic
-  generation of elimination schemes.
-- Modification of the Scheme command so you can ask for the name to be
-  automatically computed (e.g. Scheme Induction for nat Sort Set).
-- New command "Combined Scheme" to build combined mutual induction
-  principles from existing mutual induction principles.
-- New command "Scheme Equality" to build a decidable (boolean) equality
-  for simple inductive datatypes and a decision property over this equality
-  (e.g.  Scheme Equality for nat).
-- Added option "Set Equality Scheme" to make automatic the declaration
-  of the boolean equality when possible.
-- Source of universe inconsistencies now printed when option
-  "Set Printing Universes" is activated.
-- New option "Set Printing Existential Instances" for making the display of
-  existential variable instances explicit.
-- Support for option "[id1 ... idn]", and "-[id1 ... idn]", for the
-  "compute"/"cbv" reduction strategy, respectively meaning reduce only, or
-  everything but, the constants id1 ... idn. "lazy" alone or followed by
-  "[id1 ... idn]", and "-[id1 ... idn]" also supported, meaning apply
-  all of beta-iota-zeta-delta, possibly restricting delta.
-- New command "Strategy" to control the expansion of constants during
-  conversion tests. It generalizes commands Opaque and Transparent by
-  introducing a range of levels. Lower levels are assigned to constants
-  that should be expanded first.
-- New options Global and Local to Opaque and Transparent.
-- New command "Print Assumptions" to display all variables, parameters
-  or axioms a theorem or definition relies on.
-- "Add Rec LoadPath" now provides references to libraries using partially
-  qualified names (this holds also for coqtop/coqc option -R).
-- SearchAbout supports negated search criteria, reference to logical objects
-  by their notation, and more generally search of subterms.
-- "Declare ML Module" now allows to import .cmxs files when Coq is
-  compiled in native code with a version of OCaml that supports native
-  Dynlink (>= 3.11).
-- Specific sort constraints on Record now taken into account.
-- "Print LoadPath" supports a path argument to filter the display.
-
-Libraries
-
-- Several parts of the libraries are now in Type, in particular FSets,
-  SetoidList, ListSet, Sorting, Zmisc. This may induce a few
-  incompatibilities. In case of trouble while fixing existing development,
-  it may help to simply declare Set as an alias for Type (see file
-  SetIsType).
-- New arithmetical library in theories/Numbers. It contains:
-  * an abstract modular development of natural and integer arithmetics
-    in Numbers/Natural/Abstract and Numbers/Integer/Abstract
-  * an implementation of efficient computational bounded and unbounded
-    integers that can be mapped to processor native arithmetics.
-    See Numbers/Cyclic/Int31 for 31-bit integers and Numbers/Natural/BigN
-    for unbounded natural numbers and Numbers/Integer/BigZ for unbounded
-    integers.
-  * some proofs that both older libraries Arith, ZArith and NArith and
-    newer BigN and BigZ implement the abstract modular development.
-    This allows in particular BigN and BigZ to already come with a
-    large database of basic lemmas and some generic tactics (ring),
-  This library has still an experimental status, as well as the
-  processor-acceleration mechanism, but both its abstract and its
-  concrete parts are already quite usable and could challenge the use
-  of nat, N and Z in actual developments. Moreover, an extension of
-  this framework to rational numbers is ongoing, and an efficient
-  Q structure is already provided (see Numbers/Rational/BigQ), but
-  this part is currently incomplete (no abstract layer and generic
-  lemmas).
-- Many changes in FSets/FMaps. In practice, compatibility with earlier
-  version should be fairly good, but some adaptations may be required.
-  * Interfaces of unordered ("weak") and ordered sets have been factorized
-    thanks to new features of Coq modules (in particular Include), see
-    FSetInterface. Same for maps. Hints in these interfaces have been
-    reworked (they are now placed in a "set" database).
-  * To allow full subtyping between weak and ordered sets, a field
-    "eq_dec" has been added to OrderedType. The old version of OrderedType
-    is now called MiniOrderedType and functor MOT_to_OT allow to
-    convert to the new version. The interfaces and implementations
-    of sets now contain also such a "eq_dec" field.
-  * FSetDecide, contributed by Aaron Bohannon, contains a decision
-    procedure allowing to solve basic set-related goals (for instance,
-    is a point in a particular set ?). See FSetProperties for examples.
-  * Functors of properties have been improved, especially the ones about
-    maps, that now propose some induction principles. Some properties
-    of fold need less hypothesis.
-  * More uniformity in implementations of sets and maps: they all use
-    implicit arguments, and no longer export unnecessary scopes (see
-    bug #1347)
-  * Internal parts of the implementations based on AVL have evolved a
-    lot. The main files FSetAVL and FMapAVL are now much more
-    lightweight now. In particular, minor changes in some functions
-    has allowed to fully separate the proofs of operational
-    correctness from the proofs of well-balancing: well-balancing is
-    critical for efficiency, but not anymore for proving that these
-    trees implement our interfaces, hence we have moved these proofs
-    into appendix files FSetFullAVL and FMapFullAVL. Moreover, a few
-    functions like union and compare have been modified in order to be
-    structural yet efficient. The appendix files also contains
-    alternative versions of these few functions, much closer to the
-    initial Ocaml code and written via the Function framework.
-- Library IntMap, subsumed by FSets/FMaps, has been removed from
-  Coq Standard Library and moved into a user contribution Cachan/IntMap
-- Better computational behavior of some constants (eq_nat_dec and
-  le_lt_dec more efficient, Z_lt_le_dec and Positive_as_OT.compare
-  transparent, ...) (exceptional source of incompatibilities).
-- Boolean operators moved from module Bool to module Datatypes (may need
-  to rename qualified references in script and force notations || and &&
-  to be at levels 50 and 40 respectively).
-- The constructors xI and xO of type positive now have postfix notations
-  "~1" and "~0", allowing to write numbers in binary form easily, for instance
-  6 is 1~1~0 and 4*p is p~0~0 (see BinPos.v).
-- Improvements to NArith (Nminus, Nmin, Nmax), and to QArith (in particular
-  a better power function).
-- Changes in ZArith: several additional lemmas (used in theories/Numbers),
-  especially in Zdiv, Znumtheory, Zpower. Moreover, many results in
-  Zdiv have been generalized: the divisor may simply be non-null
-  instead of strictly positive (see lemmas with name ending by
-  "_full"). An alternative file ZOdiv proposes a different behavior
-  (the one of Ocaml) when dividing by negative numbers.
-- Changes in Arith: EqNat and Wf_nat now exported from Arith, some
-  constructions on nat that were outside Arith are now in (e.g. iter_nat).
-- In SetoidList, eqlistA now expresses that two lists have similar elements
-  at the same position, while the predicate previously called eqlistA
-  is now equivlistA (this one only states that the lists contain the same
-  elements, nothing more).
-- Changes in Reals:
-  * Most statement in "sigT" (including the
-    completeness axiom) are now in "sig" (in case of incompatibility,
-    use proj1_sig instead of projT1, sig instead of sigT, etc).
-  * More uniform naming scheme (identifiers in French moved to English,
-    consistent use of 0 -- zero -- instead of O -- letter O --, etc).
-  * Lemma on prod_f_SO is now on prod_f_R0.
-  * Useless hypothesis of ln_exists1 dropped.
-  * New Rlogic.v states a few logical properties about R axioms.
-  * RIneq.v extended and made cleaner.
-- Slight restructuration of the Logic library regarding choice and classical
-  logic. Addition of files providing intuitionistic axiomatizations of
-  descriptions: Epsilon.v, Description.v and IndefiniteDescription.v.
-- Definition of pred and minus made compatible with the structural
-  decreasing criterion for use in fixpoints.
-- Files Relations/Rstar.v and Relations/Newman.v moved out to the user
-  contribution repository (contribution CoC_History). New lemmas about
-  transitive closure added and some bound variables renamed (exceptional
-  risk of incompatibilities).
-- Syntax for binders in terms (e.g. for "exists") supports anonymous names.
-
-Notations, coercions, implicit arguments and type inference
-
-- More automation in the inference of the return clause of dependent
-  pattern-matching problems.
-- Experimental allowance for omission of the clauses easily detectable as
-  impossible in pattern-matching problems.
-- Improved inference of implicit arguments.
-- New options "Set Maximal Implicit Insertion", "Set Reversible Pattern
-  Implicit", "Set Strongly Strict Implicit" and "Set Printing Implicit
-  Defensive" for controlling inference and use of implicit arguments.
-- New modifier in "Implicit Arguments" to force an implicit argument to
-  be maximally inserted.
-- New modifier of "Implicit Arguments" to enrich the set of implicit arguments.
-- New options Global and Local to "Implicit Arguments" for section
-  surviving or non export outside module.
-- Level "constr" moved from 9 to 8.
-- Structure/Record now printed as Record (unless option Printing All is set).
-- Support for parametric notations defining constants.
-- Insertion of coercions below product types refrains to unfold
-  constants (possible source of incompatibility).
-- New support for fix/cofix in notations.
-
-Tactic Language
-
-- Second-order pattern-matching now working in Ltac "match" clauses
-  (syntax for second-order unification variable is "@?X").
-- Support for matching on let bindings in match context using syntax
-  "H := body" or "H := body : type".
-- Ltac accepts integer arguments (syntax is "ltac:nnn" for nnn an integer).
-- The general sequence tactical "expr_0 ; [ expr_1 | ... | expr_n ]"
-  is extended so that at most one expr_i may have the form "expr .."
-  or just "..". Also, n can be different from the number of subgoals
-  generated by expr_0. In this case, the value of expr (or idtac in
-  case of just "..") is applied to the intermediate subgoals to make
-  the number of tactics equal to the number of subgoals.
-- A name used as the name of the parameter of a lemma (like f in
-  "apply f_equal with (f:=t)") is now interpreted as a ltac variable
-  if such a variable exists (this is a possible source of
-  incompatibility and it can be fixed by renaming the variables of a
-  ltac function into names that do not clash with the lemmas
-  parameter names used in the tactic).
-- New syntax "Ltac tac ::= ..." to rebind a tactic to a new expression.
-- "let rec ... in ... " now supported for expressions without explicit
-  parameters; interpretation is lazy to the contrary of "let ... in ...";
-  hence, the "rec" keyword can be used to turn the argument of a
-  "let ... in ..." into a lazy one.
-- Patterns for hypotheses types in "match goal" are now interpreted in
-  type_scope.
-- A bound variable whose name is not used elsewhere now serves as
-  metavariable in "match" and it gets instantiated by an identifier
-  (allow e.g. to extract the name of a statement like "exists x, P x").
-- New printing of Ltac call trace for better debugging.
-
-Tactics
-
-- New tactics "apply -> term", "apply <- term", "apply -> term in
-  ident", "apply <- term in ident" for applying equivalences (iff).
-- Slight improvement of the hnf and simpl tactics when applied on
-  expressions with explicit occurrences of match or fix.
-- New tactics "eapply in", "erewrite", "erewrite in".
-- New tactics "ediscriminate", "einjection", "esimplify_eq".
-- Tactics "discriminate", "injection", "simplify_eq" now support any
-  term as argument. Clause "with" is also supported.
-- Unfoldable references can be given by notation's string rather than by name
-  in unfold.
-- The "with" arguments are now typed using informations from the current goal:
-  allows support for coercions and more inference of implicit arguments.
-- Application of "f_equal"-style lemmas works better.
-- Tactics elim, case, destruct and induction now support variants eelim,
-  ecase, edestruct and einduction.
-- Tactics destruct and induction now support the "with" option and the
-  "in" clause option. If the option "in" is used, an equality is added
-  to remember the term to which the induction or case analysis applied
-  (possible source of parsing incompatibilities when destruct or induction is
-   part of a let-in expression in Ltac; extra parentheses are then required).
-- New support for "as" clause in tactics "apply in" and "eapply in".
-- Some new intro patterns:
-  * intro pattern "?A" genererates a fresh name based on A.
-    Caveat about a slight loss of compatibility:
-    Some intro patterns don't need space between them. In particular
-    intros ?a?b used to be legal and equivalent to intros ? a ? b. Now it
-    is still legal but equivalent to intros ?a ?b.
-  * intro pattern "(A & ... & Y & Z)" synonym to "(A,....,(Y,Z)))))"
-    for right-associative constructs like /\ or exists.
-- Several syntax extensions concerning "rewrite":
-  * "rewrite A,B,C" can be used to rewrite A, then B, then C. These rewrites
-    occur only on the first subgoal: in particular, side-conditions of the
-    "rewrite A" are not concerned by the "rewrite B,C".
-  * "rewrite A by tac" allows to apply tac on all side-conditions generated by
-    the "rewrite A".
-  * "rewrite A at n" allows to select occurrences to rewrite: rewrite only
-    happen at the n-th exact occurrence of the first successful matching of
-    A in the goal.
-  * "rewrite 3 A" or "rewrite 3!A" is equivalent to "rewrite A,A,A".
-  * "rewrite !A" means rewriting A as long as possible (and at least once).
-  * "rewrite 3?A" means rewriting A at most three times.
-  * "rewrite ?A" means rewriting A as long as possible (possibly never).
-  * many of the above extensions can be combined with each other.
-- Introduction patterns better respect the structure of context in presence of
-  missing or extra names in nested disjunction-conjunction patterns [possible
-  source of rare incompatibilities].
-- New syntax "rename a into b, c into d" for "rename a into b; rename c into d"
-- New tactics "dependent induction/destruction H [ generalizing id_1 .. id_n ]"
-  to do induction-inversion on instantiated inductive families à la BasicElim.
-- Tactics "apply" and "apply in" now able to reason modulo unfolding of
-  constants (possible source of incompatibility in situations where apply
-  may fail, e.g. as argument of a try or a repeat and in a ltac function);
-  versions that do not unfold are renamed into "simple apply" and
-  "simple apply in" (usable for compatibility or for automation).
-- Tactics "apply" and "apply in" now able to traverse conjunctions and to
-  select the first matching lemma among the components of the conjunction;
-  tactic "apply" also able to apply lemmas of conclusion an empty type.
-- Tactic "apply" now supports application of several lemmas in a row.
-- Tactics "set" and "pose" can set functions using notation "(f x1..xn := c)".
-- New tactic "instantiate" (without argument).
-- Tactic firstorder "with" and "using" options have their meaning swapped for
-  consistency with auto/eauto (source of incompatibility).
-- Tactic "generalize" now supports "at" options to specify occurrences
-  and "as" options to name the quantified hypotheses.
-- New tactic "specialize H with a" or "specialize (H a)" allows to transform
-  in-place a universally-quantified hypothesis (H : forall x, T x) into its
-  instantiated form (H : T a). Nota: "specialize" was in fact there in earlier
-  versions of Coq, but was undocumented, and had a slightly different behavior.
-- New tactic "contradict H" can be used to solve any kind of goal as long as
-  the user can provide afterwards a proof of the negation of the hypothesis H.
-  If H is already a negation, say ~T, then a proof of T is asked.
-  If the current goal is a negation, say ~U, then U is saved in H afterwards,
-  hence this new tactic "contradict" extends earlier tactic "swap", which is
-  now obsolete.
-- Tactics f_equal is now done in ML instead of Ltac: it now works on any
-  equality of functions, regardless of the arity of the function.
-- New options "before id", "at top", "at bottom" for tactics "move"/"intro".
-- Some more debug of reflexive omega (romega), and internal clarifications.
-  Moreover, romega now has a variant "romega with *" that can be also used
-  on non-Z goals (nat, N, positive) via a call to a translation tactic named
-  zify (its purpose is to Z-ify your goal...). This zify may also be used
-  independently of romega.
-- Tactic "remember" now supports an "in" clause to remember only selected
-  occurrences of a term.
-- Tactic "pose proof" supports name overwriting in case of specialization of an
-  hypothesis.
-- Semi-decision tactic "jp" for first-order intuitionistic logic moved to user
-  contributions (subsumed by "firstorder").
-
-Program
-
-- Moved useful tactics in theories/Program and documented them.
-- Add Program.Basics which contains standard definitions for functional
-  programming (id, apply, flip...)
-- More robust obligation handling, dependent pattern-matching and
-  well-founded definitions.
-- New syntax " dest term as pat in term " for destructing objects using
-  an irrefutable pattern while keeping equalities (use this instead of
-  "let" in Programs).
-- Program CoFixpoint is accepted, Program Fixpoint uses the new way to infer
-  which argument decreases structurally.
-- Program Lemma, Axiom etc... now permit to have obligations in the statement
-  iff they can be automatically solved by the default tactic.
-- Renamed "Obligations Tactic" command to "Obligation Tactic".
-- New command "Preterm [ of id ]" to see the actual term fed to Coq for
-  debugging purposes.
-- New option "Transparent Obligations" to control the declaration of
-  obligations as transparent or opaque. All obligations are now transparent
-  by default, otherwise the system declares them opaque if possible.
-- Changed the notations "left" and "right" to "in_left" and "in_right" to hide
-  the proofs in standard disjunctions, to avoid breaking existing scripts when
-  importing Program. Also, put them in program_scope.
-
-Type Classes
-
-- New "Class", "Instance" and "Program Instance" commands to define
-  classes and instances documented in the reference manual.
-- New binding construct " [ Class_1 param_1 .. param_n, Class_2 ... ] "
-  for binding type classes, usable everywhere.
-- New command " Print Classes " and " Print Instances some_class " to
-  print tables for typeclasses.
-- New default eauto hint database "typeclass_instances" used by the default
-  typeclass instance search tactic.
-- New theories directory "theories/Classes" for standard typeclasses
-  declarations. Module Classes.RelationClasses is a typeclass port of
-  Relation_Definitions plus a generic development of algebra on
-  n-ary heterogeneous predicates.
-
-Setoid rewriting
-
-- Complete (and still experimental) rewrite of the tactic
-  based on typeclasses. The old interface and semantics are
-  almost entirely respected, except:
-
-  - Import Setoid is now mandatory to be able to call setoid_replace
-  and declare morphisms.
-
-  - "-->", "++>" and "==>" are now right associative notations
-  declared at level 55 in scope signature_scope.
-  Their introduction may break existing scripts that defined
-  them as notations with different levels.
-
-  - One needs to use [Typeclasses unfold [cst]] if [cst] is used
-  as an abbreviation hiding products in types of morphisms,
-  e.g. if ones redefines [relation] and declares morphisms
-  whose type mentions [relation].
-
-  - The [setoid_rewrite]'s semantics change when rewriting with
-  a lemma: it can rewrite two different instantiations of the lemma
-  at once. Use [setoid_rewrite H at 1] for (almost) the usual semantics.
-  [setoid_rewrite] will also try to rewrite under binders now, and can
-  succeed on different terms than before. In particular, it will unify under
-  let-bound variables. When called through [rewrite], the semantics are
-  unchanged though.
-
-  - [Add Morphism term : id] has different semantics when used with
-  parametric morphism: it will try to find a relation on the parameters
-  too. The behavior has also changed with respect to default relations:
-  the most recently declared Setoid/Relation will be used, the documentation
-  explains how to customize this behavior.
-
-  - Parametric Relation and Morphism are declared differently, using the
-  new [Add Parametric] commands, documented in the manual.
-
-  - Setoid_Theory is now an alias to Equivalence, scripts building objects
-  of type Setoid_Theory need to unfold (or "red") the definitions
-  of Reflexive, Symmetric and Transitive in order to get the same goals
-  as before. Scripts which introduced variables explicitely will not break.
-
-  - The order of subgoals when doing [setoid_rewrite] with side-conditions
-  is always the same: first the new goal, then the conditions.
-
-- New standard library modules Classes.Morphisms declares
-  standard morphisms on refl/sym/trans relations.
-  Classes.Morphisms_Prop declares morphisms on propositional
-  connectives and Classes.Morphisms_Relations on generalized predicate
-  connectives. Classes.Equivalence declares notations and tactics
-  related to equivalences and Classes.SetoidTactics defines the
-  setoid_replace tactics and some support for the "Add *" interface,
-  notably the tactic applied automatically before each "Add Morphism"
-  proof.
-
-- User-defined subrelations are supported, as well as higher-order morphisms
-  and rewriting under binders. The tactic is also extensible entirely in Ltac.
-  The documentation has been updated to cover these features.
-
-- [setoid_rewrite] and [rewrite] now support the [at] modifier to select
-  occurrences to rewrite, and both use the [setoid_rewrite] code, even when
-  rewriting with leibniz equality if occurrences are specified.
-
-Extraction
-
-- Improved behavior of the Caml extraction of modules: name clashes should
-  not happen anymore.
-- The command Extract Inductive has now a syntax for infix notations. This
-  allows in particular to map Coq lists and pairs onto Caml ones:
-    Extract Inductive list => list [ "[]" "(::)" ].
-    Extract Inductive prod => "(*)" [ "(,)" ].
-- In pattern matchings, a default pattern "| _ -> ..." is now used whenever
-  possible if several branches are identical. For instance, functions
-  corresponding to decidability of equalities are now linear instead of
-  quadratic.
-- A new instruction Extraction Blacklist id1 .. idn allows to prevent filename
-  conflits with existing code, for instance when extracting module List
-  to Ocaml.
-
-CoqIDE
-
-- CoqIDE font defaults to monospace so as indentation to be meaningful.
-- CoqIDE supports nested goals and any other kind of declaration in the middle
-  of a proof.
-- Undoing non-tactic commands in CoqIDE works faster.
-- New CoqIDE menu for activating display of various implicit informations.
-- Added the possibility to choose the location of tabs in coqide:
-  (in Edit->Preferences->Misc)
-- New Open and Save As dialogs in CoqIDE which filter *.v files.
-
-Tools
-
-- New stand-alone .vo files verifier "coqchk".
-- Extended -I coqtop/coqc option to specify a logical dir: "-I dir -as coqdir".
-- New coqtop/coqc option -exclude-dir to exclude subdirs for option -R.
-- The binary "parser" has been renamed to "coq-parser".
-- Improved coqdoc and dump of globalization information to give more
-  meta-information on identifiers. All categories of Coq definitions are
-  supported, which makes typesetting trivial in the generated documentation.
-  Support for hyperlinking and indexing developments in the tex output
-  has been implemented as well.
-
-Miscellaneous
-
-- Coq installation provides enough files so that Ocaml's extensions need not
-  the Coq sources to be compiled (this assumes O'Caml 3.10 and Camlp5).
-- New commands "Set Whelp Server" and "Set Whelp Getter" to customize the
-  Whelp search tool.
-- Syntax of "Test Printing Let ref" and "Test Printing If ref" changed into
-  "Test Printing Let for ref" and "Test Printing If for ref".
-- An overhauled build system (new Makefiles); see dev/doc/build-system.txt.
-- Add -browser option to configure script.
-- Build a shared library for the C part of Coq, and use it by default on
-  non-(Windows or MacOS) systems. Bytecode executables are now pure. The
-  behaviour is configurable with -coqrunbyteflags, -coqtoolsbyteflags and
-  -custom configure options.
-- Complexity tests can be skipped by setting the environment variable
-  COQTEST_SKIPCOMPLEXITY.
-
-Changes from V8.1gamma to V8.1
-==============================
-
-Bug fixes
-
-- Many bugs have been fixed (cf coq-bugs web page)
-
-Tactics
-
-- New tactics ring, ring_simplify and new tactic field now able to manage
-  power to a positive integer constant. Tactic ring on Z and R, and
-  field on R manage power (may lead to incompatibilities with V8.1gamma).
-- Tactic field_simplify now applicable in hypotheses.
-- New field_simplify_eq for simplifying field equations into ring equations.
-- Tactics ring, ring_simplify, field, field_simplify and field_simplify_eq
-  all able to apply user-given equations to rewrite monoms on the fly
-  (see documentation).
-
-Libraries
-
-- New file ConstructiveEpsilon.v defining an epsilon operator and
-  proving the axiom of choice constructively for a countable domain
-  and a decidable predicate.
-
-Changes from V8.1beta to V8.1gamma
-==================================
-
-Syntax
-
-- changed parsing precedence of let/in and fun constructions of Ltac:
-  let x := t in e1; e2 is now parsed as let x := t in (e1;e2).
-
-Language and commands
-
-- Added sort-polymorphism for definitions in Type (but finally abandonned).
-- Support for implicit arguments in the types of parameters in
-  (co-)fixpoints and (co-)inductive declarations.
-- Improved type inference: use as much of possible general information.
-  before applying irreversible unification heuristics (allow e.g. to
-  infer the predicate in "(exist _ 0 (refl_equal 0) : {n:nat | n=0 })").
-- Support for Miller-Pfenning's patterns unification in type synthesis
-  (e.g. can infer P such that P x y = phi(x,y)).
-- Support for "where" clause in cofixpoint definitions.
-- New option "Set Printing Universes" for making Type levels explicit.
-
-Tactics
-
-- Improved implementation of the ring and field tactics. For compatibility
-  reasons, the previous tactics are renamed as legacy ring and legacy field,
-  but should be considered as deprecated.
-- New declarative mathematical proof language.
-- Support for argument lists of arbitrary length in Tactic Notation.
-- [rewrite ... in H] now fails if [H] is used either in an hypothesis
-  or in the goal.
-- The semantics of [rewrite ... in *] has been slightly modified (see doc).
-- Support for "as" clause in tactic injection.
-- New forward-reasoning tactic "apply in".
-- Ltac fresh operator now builds names from a concatenation of its arguments.
-- New ltac tactic "remember" to abstract over a subterm and keep an equality
-- Support for Miller-Pfenning's patterns unification in apply/rewrite/...
-  (may lead to few incompatibilities - generally now useless tactic calls).
-
-Bug fixes
-
-- Fix for notations involving basic "match" expressions.
-- Numerous other bugs solved (a few fixes may lead to incompatibilities).
-
-
-Changes from V8.0 to V8.1beta
-=============================
-
-Logic
-
-- Added sort-polymorphism on inductive families
-- Allowance for recursively non uniform parameters in inductive types
-
-Syntax
-
-- No more support for version 7 syntax and for translation to version 8 syntax.
-- In fixpoints, the { struct ... } annotation is not mandatory any more when
-  only one of the arguments has an inductive type
-- Added disjunctive patterns in match-with patterns
-- Support for primitive interpretation of string literals
-- Extended support for Unicode ranges
-
-Vernacular commands
-
-- Added "Print Ltac qualid" to print a user defined tactic.
-- Added "Print Rewrite HintDb" to print the content of a DB used by
-  autorewrite.
-- Added "Print Canonical Projections".
-- Added "Example" as synonym of "Definition".
-- Added "Proposition" and "Corollary" as extra synonyms of "Lemma".
-- New command "Whelp" to send requests to the Helm database of proofs
-  formalized in the Calculus of Inductive Constructions.
-- Command "functional induction" has been re-implemented from the new
-  "Function" command.
-
-Ltac and tactic syntactic extensions
-
-- New primitive "external" for communication with tool external to Coq
-- New semantics for "match t with": if a clause returns a
-  tactic, it is now applied to the current goal. If it fails, the next
-  clause or next matching subterm is tried (i.e. it behaves as "match
-  goal with" does). The keyword "lazymatch" can be used to delay the
-  evaluation of tactics occurring in matching clauses.
-- Hint base names can be parametric in auto and trivial.
-- Occurrence values can be parametric in unfold, pattern, etc.
-- Added entry constr_may_eval for tactic extensions.
-- Low-priority term printer made available in ML-written tactic extensions.
-- "Tactic Notation" extended to allow notations of tacticals.
-
-Tactics
-
-- New implementation and generalization of [setoid_]* (setoid_rewrite,
-  setoid_symmetry, setoid_transitivity, setoid_reflexivity and autorewite).
-  New syntax for declaring relations and morphisms (old syntax still working
-  with minor modifications, but deprecated).
-- New implementation (still experimental) of the ring tactic with a built-in
-  notion of coefficients and a better usage of setoids.
-- New conversion tactic "vm_compute": evaluates the goal (or an hypothesis)
-  with a call-by-value strategy, using the compiled version of terms.
-- When rewriting H where H is not directly a Coq equality, search first H for
-  a registered setoid equality before starting to reduce in H. This is unlikely
-  to break any script. Should this happen nonetheless, one can insert manually
-  some "unfold ... in H" before rewriting.
-- Fixed various bugs about (setoid) rewrite ... in ... (in particular bug #5941)
-- "rewrite ... in" now accepts a clause as place where to rewrite instead of
-  juste a simple hypothesis name. For instance:
-   rewrite H in H1,H2 |- * means rewrite H in H1; rewrite H in H2; rewrite H
-   rewrite H in * |-  will do try rewrite H in Hi for all hypothesis Hi <> H.
-- Added "dependent rewrite term" and "dependent rewrite term in hyp".
-- Added "autorewrite with ... in hyp [using ...]".
-- Tactic "replace" now accepts a "by" tactic clause.
-- Added "clear - id" to clear all hypotheses except the ones depending in id.
-- The argument of Declare Left Step and Declare Right Step is now a term
-  (it used to be a reference).
-- Omega now handles arbitrary precision integers.
-- Several bug fixes in Reflexive Omega (romega).
-- Idtac can now be left implicit in a [...|...] construct: for instance,
-  [ foo | | bar ] stands for [ foo | idtac | bar ].
-- Fixed a "fold" bug (non critical but possible source of incompatibilities).
-- Added classical_left and classical_right which transforms |- A \/ B into
-  ~B |- A and ~A |- B respectively.
-- Added command "Declare Implicit Tactic" to set up a default tactic to be
-  used to solve unresolved subterms of term arguments of tactics.
-- Better support for coercions to Sortclass in tactics expecting type
-  arguments.
-- Tactic "assert" now accepts "as" intro patterns and "by" tactic clauses.
-- New tactic "pose proof" that generalizes "assert (id:=p)" with intro patterns.
-- New introduction pattern "?" for letting Coq choose a name.
-- Introduction patterns now support side hypotheses (e.g. intros [|] on
-  "(nat -> nat) -> nat" works).
-- New introduction patterns "->" and "<-" for immediate rewriting of
-  introduced hypotheses.
-- Introduction patterns coming after non trivial introduction patterns now
-  force full introduction of the first pattern (e.g. "intros [[|] p]" on
-  "nat->nat->nat" now behaves like "intros [[|?] p]")
-- Added "eassumption".
-- Added option 'using lemmas' to auto, trivial and eauto.
-- Tactic "congruence" is now complete for its intended scope (ground
-  equalities and inequalities with constructors). Furthermore, it
-  tries to equates goal and hypotheses.
-- New tactic "rtauto" solves pure propositional logic and gives a
-  reflective version of the available proof.
-- Numbering of "pattern", "unfold", "simpl", ... occurrences in "match
-  with" made consistent with the printing of the return clause after
-  the term to match in the "match-with" construct (use "Set Printing All"
-  to see hidden occurrences).
-- Generalization of induction "induction x1...xn using scheme" where
-  scheme is an induction principle with complex predicates (like the
-  ones generated by function induction).
-- Some small Ltac tactics has been added to the standard library
-  (file Tactics.v):
-  * f_equal : instead of using the different f_equalX lemmas
-  * case_eq : a "case" without loss of information. An equality
-     stating the current situation is generated in every sub-cases.
-  * swap : for a negated goal ~B and a negated hypothesis H:~A,
-     swap H asks you to prove A from hypothesis B
-  * revert : revert H is generalize H; clear H.
-
-Extraction
-
-- All type parts should now disappear instead of sometimes producing _
-  (for instance in Map.empty).
-- Haskell extraction: types of functions are now printed, better
-  unsafeCoerce mechanism, both for hugs and ghc.
-- Scheme extraction improved, see http://www.pps.jussieu.fr/~letouzey/scheme.
-- Many bug fixes.
-
-Modules
-
-- Added "Locate Module qualid" to get the full path of a module.
-- Module/Declare Module syntax made more uniform.
-- Added syntactic sugar "Declare Module Export/Import" and
-  "Module Export/Import".
-- Added syntactic sugar "Module M(Export/Import X Y: T)" and
-  "Module Type M(Export/Import X Y: T)"
-  (only for interactive definitions)
-- Construct "with" generalized to module paths:
-   T with (Definition|Module) M1.M2....Mn.l := l'.
-
-Notations
-
-- Option "format" aware of recursive notations.
-- Added insertion of spaces by default in recursive notations w/o separators.
-- No more automatic printing box in case of user-provided printing "format".
-- New notation "exists! x:A, P" for unique existence.
-- Notations for specific numerals now compatible with generic notations of
-  numerals (e.g. "1" can be used to denote the unit of a group without
-  hiding 1%nat)
-
-Libraries
-
-- New library on String and Ascii characters (contributed by L. Thery).
-- New library FSets+FMaps of finite sets and maps.
-- New library QArith on rational numbers.
-- Small extension of Zmin.V, new Zmax.v, new Zminmax.v.
-- Reworking and extension of the files on classical logic and
-  description principles (possible incompatibilities)
-- Few other improvements in ZArith potentially exceptionally breaking the
-  compatibility (useless hypothesys of Zgt_square_simpl and
-  Zlt_square_simpl removed; fixed names mentioning letter O instead of
-  digit 0; weaken premises in Z_lt_induction).
-- Restructuration of Eqdep_dec.v and Eqdep.v: more lemmas in Type.
-- Znumtheory now contains a gcd function that can compute within Coq.
-- More lemmas stated on Type in Wf.v, removal of redundant Acc_iter and
-  Acc_iter2.
-- Change of the internal names of lemmas in OmegaLemmas.
-- Acc in Wf.v and clos_refl_trans in Relation_Operators.v now rely on
-  the allowance for recursively non uniform parameters (possible
-  source of incompatibilities: explicit pattern-matching on these
-  types may require to remove the occurrence associated to their
-  recursively non uniform parameter).
-- Coq.List.In_dec has been set transparent (this may exceptionally break
-  proof scripts, set it locally opaque for compatibility).
-- More on permutations of lists in List.v and Permutation.v.
-- List.v has been much expanded.
-- New file SetoidList.v now contains results about lists seen with
-  respect to a setoid equality.
-- Library NArith has been expanded, mostly with results coming from
-  Intmap (for instance a bitwise xor), plus also a bridge between N and
-  Bitvector.
-- Intmap has been reorganized. In particular its address type "addr" is
-  now N. User contributions known to use Intmap have been adapted
-  accordingly. If you're using this library please contact us.
-  A wrapper FMapIntMap now presents Intmap as a particular implementation
-  of FMaps. New developments are strongly encouraged to use either this
-  wrapper or any other implementations of FMap instead of using directly
-  this obsolete Intmap.
-
-Tools
-
-- New semantics for coqtop options ("-batch" expects option "-top dir"
-  for loading vernac file that contains definitions).
-- Tool coq_makefile now removes custom targets that are file names in
-  "make clean"
-- New environment variable COQREMOTEBROWSER to set the command invoked
-  to start the remote browser both in Coq and coqide. Standard syntax:
-  "%s" is the placeholder for the URL.
-
-
-Changes from V8.0beta to V8.0
-=============================
-
-Vernacular commands
-
-- New option "Set Printing All" to deactivate all high-level forms of
-  printing (implicit arguments, coercions, destructing let,
-  if-then-else, notations, projections)
-- "Functional Scheme" and "Functional Induction" extended to polymorphic
-  types and dependent types
-- Notation now allows recursive patterns, hence recovering parts of the
-  fonctionalities of pre-V8 Grammar/Syntax commands
-- Command "Print." discontinued.
-- Redundant syntax "Implicit Arguments On/Off" discontinued
-
-New syntax
-
-- Semantics change of the if-then-else construction in new syntax:
-  "if c then t1 else t2" now stands for
-  "match c with c1 _ ... _ => t1 | c2 _ ... _ => t2 end"
-  with no dependency of t1 and t2 in the arguments of the constructors;
-  this may cause incompatibilities for files translated using coq 8.0beta
-
-Interpretation scopes
-
-- Delimiting key %bool for bool_scope added
-- Import no more needed to activate argument scopes from a module
-
-Tactics and the tactic Language
-
-- Semantics of "assert" is now consistent with the reference manual
-- New tactics stepl and stepr for chaining transitivity steps
-- Tactic "replace ... with ... in" added
-- Intro patterns now supported in Ltac (parsed with prefix "ipattern:")
-
-Executables and tools
-
-- Added option -top to change the name of the toplevel module "Top"
-- Coqdoc updated to new syntax and now part of Coq sources
-- XML exportation tool now exports the structure of vernacular files
-  (cf chapter 13 in the reference manual)
-
-User contributions
-
-- User contributions have been updated to the new syntax
-
-Bug fixes
-
-- Many bugs have been fixed (cf coq-bugs web page)
-
-Changes from V8.0beta old syntax to V8.0beta
-============================================
-
-New concrete syntax
-
-- A completely new syntax for terms
-- A more uniform syntax for tactics and the tactic language
-- A few syntactic changes for vernacular commands
-- A smart automatic translator translating V8.0 files in old syntax to
-  files valid for V8.0
-
-Syntax extensions
-
-- "Grammar" for terms disappears
-- "Grammar" for tactics becomes "Tactic Notation"
-- "Syntax" disappears
-- Introduction of a notion of interpretation scope allowing to use the
-  same notations in various contexts without using specific delimiters
-  (e.g the same expression "4<=3+x" is interpreted either in "nat",
-  "positive", "N" (previously "entier"), "Z", "R", depending on which
-  interpretation scope is currently open) [see documentation for details]
-- Notation now mandatorily requires a precedence and associativity
-  (default was to set precedence to 1 and associativity to none)
-
-Revision of the standard library
-
-- Many lemmas and definitions names have been made more uniform mostly
-  in Arith, NArith, ZArith and Reals (e.g : "times" -> "Pmult",
-  "times_sym" -> "Pmult_comm", "Zle_Zmult_pos_right" ->
-  "Zmult_le_compat_r", "SUPERIEUR" -> "Gt", "ZERO" -> "Z0")
-- Order and names of arguments of basic lemmas on nat, Z, positive and R
-  have been made uniform.
-- Notions of Coq initial state are declared with (strict) implicit arguments
-- eq merged with eqT: old eq disappear, new eq (written =) is old eqT
-  and new eqT is syntactic sugar for new eq (notation == is an alias
-  for = and is written as it, exceptional source of incompatibilities)
-- Similarly, ex, ex2, all, identity are merged with exT, exT2, allT, identityT
-- Arithmetical notations for nat, positive, N, Z, R, without needing
-  any backquote or double-backquotes delimiters.
-- In Lists: new concrete notations; argument of nil is now implicit
-- All changes in the library are taken in charge by the translator
-
-Semantical changes during translation
-
-- Recursive keyword set by default (and no longer needed) in Tactic Definition
-- Set Implicit Arguments is strict by default in new syntax
-- reductions in hypotheses of the form "... in H" now apply to the type
-  also if H is a local definition
-- etc
-
-Gallina
-
-- New syntax of the form "Inductive bool : Set := true, false : bool." for
-  enumerated types
-- Experimental syntax of the form p.(fst) for record projections
-  (activable with option "Set Printing Projections" which is
-   recognized by the translator)
-
-Known problems of the automatic translation
-
-- iso-latin-1 characters are no longer supported: move your files to
-  7-bits ASCII or unicode before translation (swith to unicode is
-  automatically done if a file is loaded and saved again by coqide)
-- Renaming in ZArith: incompatibilities in Coq user contribs due to
-  merging names INZ, from Reals, and inject_nat.
-- Renaming and new lemmas in ZArith: may clash with names used by users
-- Restructuration of ZArith: replace requirement of specific modules
-  in ZArith by "Require Import ZArith_base" or "Require Import ZArith"
-- Some implicit arguments must be made explicit before translation: typically
-  for "length nil", the implicit argument of length must be made explicit
-- Grammar rules, Infix notations and V7.4 Notations must be updated wrt the
-  new scheme for syntactic extensions (see translator documentation)
-- Unsafe for annotation Cases when constructors coercions are used or when
-  annotations are eta-reduced predicates
-
-
-Changes from V7.4 to V8.0beta old syntax
-========================================
-
-Logic
-
-- Set now predicative by default
-- New option -impredicative-set to set Set impredicative
-- The standard library doesn't need impredicativity of Set and is
-  compatible with the classical axioms which contradict Set impredicativity
-
-Syntax for arithmetic
-
-- Notation "=" and "<>" in Z and R are no longer implicitly in Z or R
-  (with possible introduction of a coercion), use <Z>...=... or
-  <Z>...<>... instead
-- Locate applied to a simple string (e.g. "+") searches for all
-  notations containing this string
-
-Vernacular commands
-
-- "Declare ML Module" now allows to import .cma files. This avoids to use a
-   bunch of "Declare ML Module" statements when using several ML files.
-- "Set Printing Width n" added, allows to change the size of width printing.
-- "Implicit Variables Type x,y:t" (new syntax: "Implicit Types x y:t")
-  assigns default types for binding variables.
-- Declarations of Hints and Notation now accept a "Local" flag not to
-  be exported outside the current file even if not in section
-- "Print Scopes" prints all notations
-- New command "About name" for light printing of type, implicit arguments, etc.
-- New command "Admitted" to declare incompletely proven statement as axioms
-- New keyword "Conjecture" to declare an axiom intended to be provable
-- SearchAbout can now search for lemmas referring to more than one constant
-  and on substrings of the name of the lemma
-- "Print Implicit" displays the implicit arguments of a constant
-- Locate now searches for all names having a given suffix
-- New command "Functional Scheme" for building an induction principle
-  from a function defined by case analysis and fix.
-
-Commands
-
-- new coqtop/coqc option -dont-load-proofs not to load opaque proofs in memory
-
-Implicit arguments
-
-- Inductive in sections declared with implicits now "discharged" with
-  implicits (like constants and variables)
-- Implicit Arguments flags are now synchronous with reset
-- New switch "Unset/Set Printing Implicits" (new syntax: "Unset/Set Printing
-  Implicit") to globally control printing of implicits
-
-Grammar extensions
-
-- Many newly supported UTF-8 encoded unicode blocks
-  - Greek letters (0380-03FF), Hebrew letters (U05D0-05EF), letter-like
-  symbols (2100-214F, that includes double N,Z,Q,R), prime
-  signs (from 2080-2089) and characters from many written languages
-  are valid in identifiers
-  - mathematical operators (2200-22FF), supplemental mathematical
-  operators (2A00-2AFF), miscellaneous technical (2300-23FF that
-  includes sqrt symbol), miscellaneous symbols (2600-26FF), arrows
-  (2190-21FF and 2900-297F), invisible mathematical operators (from
-  2080-2089), ... are valid symbols
-
-Library
-
-- New file about the factorial function in Arith
-- An additional elimination Acc_iter for Acc, simplier than Acc_rect.
-  This new elimination principle is used for definition well_founded_induction.
-- New library NArith on binary natural numbers
-- R is now of type Set
-- Restructuration in ZArith library
-  - "true_sub" used in Zplus now a definition, not a local one (source
-  of incompatibilities in proof referring to true_sub, may need extra Unfold)
-  - Some lemmas about minus moved from fast_integer to Arith/Minus.v
-  (le_minus, lt_mult_left) (theoretical source of incompatibilities)
-  - Several lemmas moved from auxiliary.v and zarith_aux.v to
-  fast_integer.v (theoretical source of incompatibilities)
-  - Variables names of iff_trans changed (source of incompatibilities)
-  - ZArith lemmas named OMEGA something or fast_ something, and lemma new_var
-    are now out of ZArith (except OMEGA2)
-  - Redundant ZArith lemmas have been renamed: for the following pairs,
-  use the second name (Zle_Zmult_right2, Zle_mult_simpl), (OMEGA2,
-  Zle_0_plus), (Zplus_assoc_l, Zplus_assoc), (Zmult_one, Zmult_1_n),
-  (Zmult_assoc_l, Zmult_assoc), (Zmult_minus_distr, Zmult_Zminus_distr_l)
-  (add_un_double_moins_un_xO, is_double_moins_un),
-  (Rlt_monotony_rev,Rlt_monotony_contra) (source of incompatibilities)
-- Few minor changes (no more implicit arguments in
-  Zmult_Zminus_distr_l and Zmult_Zminus_distr_r, lemmas moved from
-  Zcomplements to other files) (rare source of incompatibilities)
-- New lemmas provided by users added
-
-Tactic language
-
-- Fail tactic now accepts a failure message
-- Idtac tactic now accepts a message
-- New primitive tactic "FreshId" (new syntax: "fresh") to generate new names
-- Debugger prints levels of calls
-
-Tactics
-
-- Replace can now replace proofs also
-- Fail levels are now decremented at "Match Context" blocks only and
-  if the right-hand-side of "Match term With" are tactics, these
-  tactics are never evaluated immediately and do not induce
-  backtracking (in contrast with "Match Context")
-- Quantified names now avoid global names of the current module (like
-  Intro names did) [source of rare incompatibilities: 2 changes in the set of
-  user contribs]
-- NewDestruct/NewInduction accepts intro patterns as introduction names
-- NewDestruct/NewInduction now work for non-inductive type using option "using"
-- A NewInduction naming bug for inductive types with functional
-  arguments (e.g. the accessibility predicate) has been fixed (source
-  of incompatibilities)
-- Symmetry now applies to hypotheses too
-- Inversion now accept option "as [ ... ]" to name the hypotheses
-- Contradiction now looks also for contradictory hypotheses stating ~A and A
-  (source of incompatibility)
-- "Contradiction c" try to find an hypothesis in context which
-  contradicts the type of c
-- Ring applies to new library NArith (require file NArithRing)
-- Field now works on types in Set
-- Auto with reals now try to replace le by ge (Rge_le is no longer an
-  immediate hint), resulting in shorter proofs
-- Instantiate now works in hyps (syntax : Instantiate in ...)
-- Some new tactics : EConstructor, ELeft, Eright, ESplit, EExists
-- New tactic "functional induction" to perform case analysis and
-  induction following the definition of a function.
-- Clear now fails when trying to remove a local definition used by
-  a constant appearing in the current goal
-
-Extraction (See details in plugins/extraction/CHANGES)
-
-- The old commands: 	(Recursive) Extraction Module M.
-  are now:              (Recursive) Extraction Library M.
-  To use these commands, M should come from a library M.v
-- The other syntax Extraction & Recursive Extraction now accept
-  module names as arguments.
-
-Bugs
-
-- see coq-bugs server for the complete list of fixed bugs
-
-Miscellaneous
-
-- Implicit parameters of inductive types definition now taken into
-  account for infering other implicit arguments
-
-Incompatibilities
-
-- Persistence of true_sub (4 incompatibilities in Coq user contributions)
-- Variable names of some constants changed for a better uniformity (2 changes
-  in Coq user contributions)
-- Naming of quantified names in goal now avoid global names (2 occurrences)
-- NewInduction naming for inductive types with functional arguments
-  (no incompatibility in Coq user contributions)
-- Contradiction now solve more goals (source of 2 incompatibilities)
-- Merge of eq and eqT may exceptionally result in subgoals now
-  solved automatically
-- Redundant pairs of ZArith lemmas may have different names: it may
-  cause "Apply/Rewrite with" to fail if using the first name of a pair
-  of redundant lemmas (this is solved by renaming the variables bound by
-  "with"; 3 incompatibilities in Coq user contribs)
-- ML programs referring to constants from fast_integer.v must use
-  "Coqlib.gen_constant_modules Coqlib.zarith_base_modules" instead
diff --git a/doc/sphinx/changes.rst b/doc/sphinx/changes.rst
index 6e560f68b8..0620e09a4a 100644
--- a/doc/sphinx/changes.rst
+++ b/doc/sphinx/changes.rst
@@ -5,6 +5,9 @@ Recent changes
 Version 8.9
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 |Coq| version 8.9 contains the result of refinements and stabilization
 of features and deprecations or removals of deprecated features,
 cleanups of the internals of the system and API along with a few new
@@ -149,9 +152,227 @@ engineer working with Maxime Dénès in the |Coq| consortium.
 | Matthieu Sozeau for the |Coq| development team
 |
 
+Details of changes
+~~~~~~~~~~~~~~~~~~
+
+Kernel
+
+- Mutually defined records are now supported.
+
+Notations
+
+- New support for autonomous grammars of terms, called "custom
+  entries" (see chapter "Syntax extensions" of the reference manual).
+
+- Deprecated compatibility notations will actually be removed in the
+  next version of Coq.  Uses of these notations are generally easy to
+  fix thanks to the hint contained in the deprecation warnings. For
+  projects that require more than a handful of such fixes, there is [a
+  script](https://gist.github.com/JasonGross/9770653967de3679d131c59d42de6d17#file-replace-notations-py)
+  that will do it automatically, using the output of coqc. The script
+  contains documentation on its usage in a comment at the top.
+
+- When several notations are available for the same expression,
+  priority is given to latest notations defined in the scopes being
+  opened, in order, rather than to the latest notations defined
+  independently of whether they are in an opened scope or not.
+
+Tactics
+
+- Added toplevel goal selector `!` which expects a single focused goal.
+  Use with `Set Default Goal Selector` to force focusing before tactics
+  are called.
+
+- The undocumented "nameless" forms `fix N`, `cofix` that were
+  deprecated in 8.8 have been removed from Ltac's syntax; please use
+  `fix ident N/cofix ident` to explicitly name the (co)fixpoint
+  hypothesis to be introduced.
+
+- Introduction tactics `intro`/`intros` on a goal that is an
+  existential variable now force a refinement of the goal into a
+  dependent product rather than failing.
+
+- Support for `fix`/`cofix` added in Ltac `match` and `lazymatch`.
+
+- Ltac backtraces now include trace information about tactics
+  called by OCaml-defined tactics.
+
+- Option `Ltac Debug` now applies also to terms built using Ltac functions.
+
+- Deprecated the `Implicit Tactic` family of commands.
+
+- The default program obligation tactic uses a bounded proof search
+  instead of an unbounded and potentially non-terminating one now
+  (source of incompatibility).
+
+- The `simple apply` tactic now respects the `Opaque` flag when called from
+  Ltac (`auto` still does not respect it).
+
+- Tactic `constr_eq` now adds universe constraints needed for the
+  identity to the context (it used to ignore them). New tactic
+  `constr_eq_strict` checks that the required constraints already hold
+  without adding new ones. Preexisting tactic `constr_eq_nounivs` can
+  still be used if you really want to ignore universe constraints.
+
+- Tactics and tactic notations now understand the `deprecated` attribute.
+- The `fourier` tactic has been removed. Please now use `lra` instead. You
+  may need to add `Require Import Lra` to your developments. For compatibility,
+  we now define `fourier` as a deprecated alias of `lra`.
+
+- The `romega` tactics have been deprecated; please use `lia` instead.
+
+Focusing
+
+- Focusing bracket `{` now supports named goal selectors,
+  e.g. `[x]: {` will focus on a goal (existential variable) named `x`.
+  As usual, unfocus with `}` once the sub-goal is fully solved.
+
+Specification language
+
+- A fix to unification (which was sensitive to the ascii name of
+  variables) may occasionally change type inference in incompatible
+  ways, especially regarding the inference of the return clause of `match`.
+
+Standard Library
+
+- Added `Ascii.eqb` and `String.eqb` and the `=?` notation for them,
+  and proved some lemmas about them.  Note that this might cause
+  incompatibilities if you have, e.g., `string_scope` and `Z_scope` both
+  open with `string_scope` on top, and expect `=?` to refer to `Z.eqb`.
+  Solution: wrap `_ =? _` in `(_ =? _)%Z` (or whichever scope you
+  want).
+
+- Added `Ndigits.N2Bv_sized`, and proved some lemmas about it.
+  Deprecated `Ndigits.N2Bv_gen`.
+
+- The scopes `int_scope` and `uint_scope` have been renamed to
+  `dec_int_scope` and `dec_uint_scope`, to clash less with ssreflect
+  and other packages.  They are still delimited by `%int` and `%uint`.
+
+- Syntax notations for `string`, `ascii`, `Z`, `positive`, `N`, `R`,
+  and `int31` are no longer available merely by `Require`ing the files
+  that define the inductives.  You must `Import` `Coq.Strings.String.StringSyntax`
+  (after `Require` `Coq.Strings.String`), `Coq.Strings.Ascii.AsciiSyntax` (after
+  `Require` `Coq.Strings.Ascii`), `Coq.ZArith.BinIntDef`, `Coq.PArith.BinPosDef`,
+  `Coq.NArith.BinNatDef`, `Coq.Reals.Rdefinitions`, and
+  `Coq.Numbers.Cyclic.Int31.Int31`, respectively, to be able to use
+  these notations.  Note that passing `-compat 8.8` or issuing
+  `Require Import Coq.Compat.Coq88` will make these notations
+  available.  Users wishing to port their developments automatically
+  may download `fix.py` from
+  <https://gist.github.com/JasonGross/5d4558edf8f5c2c548a3d96c17820169>
+  and run a command like `while true; do make -Okj 2>&1 |
+  /path/to/fix.py; done` and get a cup of coffee.  (This command must
+  be manually interrupted once the build finishes all the way though.
+  Note also that this method is not fail-proof; you may have to adjust
+  some scopes if you were relying on string notations not being
+  available even when `string_scope` was open.)
+
+- Numeral syntax for `nat` is no longer available without loading the
+  entire prelude (`Require Import Coq.Init.Prelude`).  This only
+  impacts users running Coq without the init library (`-nois` or
+  `-noinit`) and also issuing `Require Import Coq.Init.Datatypes`.
+
+Tools
+
+- Coq_makefile lets one override or extend the following variables from
+  the command line: `COQFLAGS`, `COQCHKFLAGS`, `COQDOCFLAGS`.
+  `COQFLAGS` is now entirely separate from `COQLIBS`, so in custom Makefiles
+  `$(COQFLAGS)` should be replaced by `$(COQFLAGS) $(COQLIBS)`.
+
+- Removed the `gallina` utility (extracts specification from Coq vernacular files).
+  If you would like to maintain this tool externally, please contact us.
+
+- Removed the Emacs modes distributed with Coq. You are advised to
+  use [Proof-General](https://proofgeneral.github.io/) (and optionally
+  [Company-Coq](https://github.com/cpitclaudel/company-coq)) instead.
+  If your use case is not covered by these alternative Emacs modes,
+  please open an issue. We can help set up external maintenance as part
+  of Proof-General, or independently as part of coq-community.
+
+Vernacular Commands
+
+- Removed deprecated commands `Arguments Scope` and `Implicit Arguments`
+  (not the option). Use the `Arguments` command instead.
+- Nested proofs may be enabled through the option `Nested Proofs Allowed`.
+  By default, they are disabled and produce an error. The deprecation
+  warning which used to occur when using nested proofs has been removed.
+- Added option `Uniform Inductive Parameters` which abstracts over parameters
+  before typechecking constructors, allowing to write for example
+  `Inductive list (A : Type) := nil : list | cons : A -> list -> list.`
+- New `Set Hint Variables/Constants Opaque/Transparent` commands for setting
+  globally the opacity flag of variables and constants in hint databases,
+  overwritting the opacity set of the hint database.
+- Added generic syntax for "attributes", as in:
+  `#[local] Lemma foo : bar.`
+- Added the `Numeral Notation` command for registering decimal numeral
+  notations for custom types
+- The `Set SsrHave NoTCResolution` command no longer has special global
+  scope. If you want the previous behavior, use `Global Set SsrHave
+  NoTCResolution`.
+- Multiple sections with the same name are allowed.
+
+Coq binaries and process model
+
+- Before 8.9, Coq distributed a single `coqtop` binary and a set of
+  dynamically loadable plugins that used to take over the main loop
+  for tasks such as IDE language server or parallel proof checking.
+
+  These plugins have been turned into full-fledged binaries so each
+  different process has associated a particular binary now, in
+  particular `coqidetop` is the CoqIDE language server, and
+  `coq{proof,tactic,query}worker` are in charge of task-specific and
+  parallel proof checking.
+
+SSReflect
+
+- The implementation of delayed clear switches in intro patterns
+  is now simpler to explain:
+
+  1. The immediate effect of a clear switch like `{x}` is to rename the
+     variable `x` to `_x_` (i.e. a reserved identifier that cannot be mentioned
+     explicitly)
+  2. The delayed effect of `{x}` is that `_x_` is cleared at the end of the intro
+     pattern
+  3. A clear switch immediately before a view application like `{x}/v` is
+     translated to `/v{x}`.
+
+  In particular, the third rule lets one write `{x}/v` even if `v` uses the variable `x`:
+  indeed the view is executed before the renaming.
+
+- An empty clear switch is now accepted in intro patterns before a
+  view application whenever the view is a variable.
+  One can now write `{}/v` to mean `{v}/v`.  Remark that `{}/x` is very similar
+  to the idiom `{}e` for the rewrite tactic (the equation `e` is used for
+  rewriting and then discarded).
+
+Standard Library
+
+- There are now conversions between `string` and `positive`, `Z`,
+  `nat`, and `N` in binary, octal, and hex.
+
+Display diffs between proof steps
+
+- `coqtop` and `coqide` can now highlight the differences between proof steps
+  in color. This can be enabled from the command line or the
+  `Set Diffs "on"/"off"/"removed"` command. Please see the documentation for
+  details.  Showing diffs in Proof General requires small changes to PG
+  (under discussion).
+
+Notations
+
+- Added `++` infix for `VectorDef.append`.
+  Note that this might cause incompatibilities if you have, e.g., `list_scope`
+  and `vector_scope` both open with `vector_scope` on top, and expect `++` to
+  refer to `app`.
+  Solution: wrap `_ ++ _` in `(_ ++ _)%list` (or whichever scope you want).
+
 Version 8.8
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 |Coq| version 8.8 contains the result of refinements and stabilization of
 features and deprecations, cleanups of the internals of the system along
 with a few new features. The main user visible changes are:
@@ -256,9 +477,269 @@ The contacts of the Coq Consortium are Yves Bertot and Maxime Dénès.
 | Matthieu Sozeau for the |Coq| development team
 |
 
+Details of changes in 8.8+beta1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Kernel
+
+- Support for template polymorphism for definitions was removed. May trigger
+  more "universe inconsistency" errors in rare occasions.
+- Fixpoints are no longer allowed on non-recursive inductive types.
+
+Notations
+
+- Recursive notations with the recursive pattern repeating on the
+  right (e.g. "( x ; .. ; y ; z )") now supported.
+- Notations with a specific level for the leftmost nonterminal,
+  when printing-only, are supported.
+- Notations can now refer to the syntactic category of patterns (as in
+  "fun 'pat =>" or "match p with pat => ... end"). Two variants are
+  available, depending on whether a single variable is considered as a
+  pattern or not.
+- Recursive notations now support ".." patterns with several
+  occurrences of the recursive term or binder, possibly mixing terms
+  and binders, possibly in reverse left-to-right order.
+- "Locate" now working also on notations of the form "x + y" (rather
+  than "_ + _").
+
+Specification language
+
+- When printing clauses of a "match", clauses with same right-hand
+  side are factorized and the last most factorized clause with no
+  variables, if it exists, is turned into a default clause.
+  Use "Unset Printing Allow Default Clause" do deactivate printing
+  of a default clause.
+  Use "Unset Printing Factorizable Match Patterns" to deactivate
+  factorization of clauses with same right-hand side.
+
+Tactics
+
+- On Linux, "native_compute" calls can be profiled using the "perf"
+  utility. The command "Set NativeCompute Profiling" enables
+  profiling, and "Set NativeCompute Profile Filename" customizes
+  the profile filename.
+- The tactic "omega" is now aware of the bodies of context variables
+  such as "x := 5 : Z" (see #1362). This could be disabled via
+  Unset Omega UseLocalDefs.
+- The tactic "romega" is also aware now of the bodies of context variables.
+- The tactic "zify" resp. "omega with N" is now aware of N.pred.
+- Tactic "decide equality" now able to manage constructors which
+  contain proofs.
+- Added tactics reset ltac profile, show ltac profile (and variants)
+- Added tactics restart_timer, finish_timing, and time_constr as an
+  experimental way of timing Ltac's evaluation phase
+- Added tactic optimize_heap, analogous to the Vernacular Optimize
+  Heap, which performs a major garbage collection and heap compaction
+  in the OCaml run-time system.
+- The tactics "dtauto", "dintuition", "firstorder" now handle inductive types
+  with let bindings in the parameters.
+- The tactic ``dtauto`` now handles some inductives such as
+  ``@sigT A (fun _ => B)`` as non-dependent conjunctions.
+- A bug fixed in ``rewrite H in *`` and ``rewrite H in * |-`` may cause a
+  few rare incompatibilities (it was unintendedly recursively
+  rewriting in the side conditions generated by H).
+- Added tactics "assert_succeeds tac" and "assert_fails tac" to ensure
+  properties of the executation of a tactic without keeping the effect
+  of the execution.
+- `vm_compute` now supports existential variables.
+- Calls to `shelve` and `give_up` within calls to tactic `refine` now working.
+- Deprecated tactic `appcontext` was removed.
+
+Focusing
+
+- Focusing bracket `{` now supports single-numbered goal selector,
+  e.g. `2: {` will focus on the second sub-goal. As usual, unfocus
+  with `}` once the sub-goal is fully solved.
+  The `Focus` and `Unfocus` commands are now deprecated.
+
+Vernacular Commands
+
+- Proofs ending in "Qed exporting ident, .., ident" are not supported
+  anymore. Constants generated during `abstract` are kept private to the
+  local environment.
+- The deprecated Coercion Local, Open Local Scope, Notation Local syntax
+  was removed. Use Local as a prefix instead.
+- For the Extraction Language command, "OCaml" is spelled correctly.
+  The older "Ocaml" is still accepted, but deprecated.
+- Using “Require” inside a section is deprecated.
+- An experimental command "Show Extraction" allows to extract the content
+  of the current ongoing proof (grant wish #4129).
+- Coercion now accepts the type of its argument to be "Prop" or "Type".
+- The "Export" modifier can now be used when setting and unsetting options, and
+  will result in performing the same change when the module corresponding the
+  command is imported.
+- The `Axiom` command does not automatically declare axioms as instances when
+  their type is a class. Previous behavior can be restored using `Set
+  Typeclasses Axioms Are Instances`.
+
+Universes
+
+- Qualified naming of global universes now works like other namespaced
+  objects (e.g. constants), with a separate namespace, inside and across
+  module and library boundaries. Global universe names introduced in an
+  inductive / constant / Let declaration get qualified with the name of
+  the declaration.
+- Universe cumulativity for inductive types is now specified as a
+  variance for each polymorphic universe. See the reference manual for
+  more information.
+- Inference of universe constraints with cumulative inductive types
+  produces more general constraints. Unsetting new option Cumulativity
+  Weak Constraints produces even more general constraints (but may
+  produce too many universes to be practical).
+- Fix #5726: Notations that start with `Type` now support universe instances
+  with `@{u}`.
+- `with Definition` now understands universe declarations
+  (like `@{u| Set < u}`).
+
+Tools
+
+- Coq can now be run with the option -mangle-names to change the auto-generated
+  name scheme. This is intended to function as a linter for developments that
+  want to be robust to changes in auto-generated names. This feature is experimental,
+  and may change or disappear without warning.
+- GeoProof support was removed.
+
+Checker
+
+- The checker now accepts filenames in addition to logical paths.
+
+CoqIDE
+
+- Find and Replace All report the number of occurrences found; Find indicates
+  when it wraps.
+
+coqdep
+
+- Learned to read -I, -Q, -R and filenames from _CoqProject files.
+  This is used by coq_makefile when generating dependencies for .v
+  files (but not other files).
+
+Documentation
+
+- The Coq FAQ, formerly located at https://coq.inria.fr/faq, has been
+  moved to the GitHub wiki section of this repository; the main entry
+  page is https://github.com/coq/coq/wiki/The-Coq-FAQ.
+- Documentation: a large community effort resulted in the migration
+  of the reference manual to the Sphinx documentation tool. The result
+  is partially integrated in this version.
+
+Standard Library
+
+- New libraries Coq.Init.Decimal, Coq.Numbers.DecimalFacts,
+  Coq.Numbers.DecimalNat, Coq.Numbers.DecimalPos,
+  Coq.Numbers.DecimalN, Coq.Numbers.DecimalZ,
+  Coq.Numbers.DecimalString providing a type of decimal numbers, some
+  facts about them, and conversions between decimal numbers and nat,
+  positive, N, Z, and string.
+- Added [Coq.Strings.String.concat] to concatenate a list of strings
+  inserting a separator between each item
+- Notation `'` for Zpos in QArith was removed.
+
+- Some deprecated aliases are now emitting warnings when used.
+
+Compatibility support
+
+- Support for compatibility with versions before 8.6 was dropped.
+
+Options
+
+- The following deprecated options have been removed:
+
+  + `Refolding Reduction`
+  + `Standard Proposition Elimination`
+  + `Dependent Propositions Elimination`
+  + `Discriminate Introduction`
+  + `Shrink Abstract`
+  + `Tactic Pattern Unification`
+  + `Intuition Iff Unfolding`
+  + `Injection L2R Pattern Order`
+  + `Record Elimination Schemes`
+  + `Match Strict`
+  + `Tactic Compat Context`
+  + `Typeclasses Legacy Resolution`
+  + `Typeclasses Module Eta`
+  + `Typeclass Resolution After Apply`
+
+Details of changes in 8.8.0
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Tools
+
+- Asynchronous proof delegation policy was fixed. Since version 8.7
+  Coq was ignoring previous runs and the `-async-proofs-delegation-threshold`
+  option did not have the expected behavior.
+
+Tactic language
+
+- The undocumented "nameless" forms `fix N`, `cofix` have been
+  deprecated; please use `fix ident N /cofix ident` to explicitely
+  name the (co)fixpoint hypothesis to be introduced.
+
+Documentation
+
+- The reference manual is now fully ported to Sphinx.
+
+Other small deprecations and bug fixes.
+
+Details of changes in 8.8.1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Kernel
+
+- Fix a critical bug with cofixpoints and `vm_compute`/`native_compute` (#7333).
+- Fix a critical bug with modules and algebraic universes (#7695)
+- Fix a critical bug with inlining of polymorphic constants (#7615).
+- Fix a critical bug with universe polymorphism and `vm_compute` (#7723). Was
+  present since 8.5.
+
+Notations
+
+- Fixed unexpected collision between only-parsing and only-printing
+  notations (issue #7462).
+
+Windows installer
+
+- The Windows installer now includes external packages Ltac2 and Equations
+  (it included the Bignums package since 8.8+beta1).
+
+Many other bug fixes, documentation improvements (including fixes of
+regressions due to the Sphinx migration), and user message improvements
+(for details, see the 8.8.1 milestone at
+https://github.com/coq/coq/milestone/13?closed=1).
+
+Details of changes in 8.8.2
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Documentation
+
+- A PDF version of the reference manual is available once again.
+
+Tools
+
+- The coq-makefile targets `print-pretty-timed`, `print-pretty-timed-diff`,
+  and `print-pretty-single-time-diff` now correctly label the "before" and
+  "after" columns, rather than swapping them.
+
+Kernel
+
+- The kernel does not tolerate capture of global universes by
+  polymorphic universe binders, fixing a soundness break (triggered
+  only through custom plugins)
+
+Windows installer
+
+- The Windows installer now includes many more external packages that can be
+  individually selected for installation.
+
+Many other bug fixes and lots of documentation improvements (for details,
+see the 8.8.2 milestone at https://github.com/coq/coq/milestone/15?closed=1).
+
 Version 8.7
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 |Coq| version 8.7 contains the result of refinements, stabilization of features
 and cleanups of the internals of the system along with a few new features. The
 main user visible changes are:
@@ -362,9 +843,258 @@ system, is now upcoming and will rely on Inria’s newly created Foundation.
 | Matthieu Sozeau and the |Coq| development team
 |
 
+Details of changes in 8.7+beta1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Tactics
+
+- New tactic "extensionality in H" which applies (possibly dependent)
+  functional extensionality in H supposed to be a quantified equality
+  until giving a bare equality.
+
+- New tactic ``inversion_sigma`` which turns equalities of dependent
+  pairs (e.g., ``existT P x p = existT P y q``, frequently left over by
+  ``inversion`` on a dependent type family) into pairs of equalities
+  (e.g., a hypothesis ``H : x = y`` and a hypothesis of type ``rew H in p = q``);
+  these hypotheses can subsequently be simplified using
+  ``subst``, without ever invoking any kind of axiom asserting
+  uniqueness of identity proofs. If you want to explicitly specify the
+  hypothesis to be inverted, or name the generated hypotheses, you can
+  invoke ``induction H as [H1 H2] using eq_sigT_rect``.  The tactic also
+  works for ``sig``, ``sigT2``, and ``sig2``, and there are similar
+  ``eq_sig*_rect`` induction lemmas.
+
+- Tactic "specialize with ..." now accepts any partial bindings.
+  Missing bindings are either solved by unification or left quantified
+  in the hypothesis.
+
+- New representation of terms that statically ensure stability by
+  evar-expansion. This has several consequences.
+
+  * In terms of performance, this adds a cost to every term destructuration,
+    but at the same time most eager evar normalizations were removed, which
+    couterbalances this drawback and even sometimes outperforms the old
+    implementation. For instance, many operations that would require O(n)
+    normalization of the term are now O(1) in tactics. YMMV.
+
+  * This triggers small changes in unification, which was not evar-insensitive.
+    Most notably, the new implementation recognizes Miller patterns that were
+    missed before because of a missing normalization step. Hopefully this should
+    be fairly uncommon.
+
+- Tactic "auto with real" can now discharge comparisons of literals.
+
+- The types of variables in patterns of "match" are now
+  beta-iota-reduced after type-checking. This has an impact on the
+  type of the variables that the tactic "refine" introduces in the
+  context, producing types a priori closer to the expectations.
+
+- In "Tactic Notation" or "TACTIC EXTEND", entry "constr_with_bindings"
+  now uses type classes and rejects terms with unresolved holes, like
+  entry "constr" does. To get the former behavior use
+  "open_constr_with_bindings" (possible source of incompatibility).
+
+- New e-variants eassert, eenough, epose proof, eset, eremember, epose
+  which behave like the corresponding variants with no "e" but turn
+  unresolved implicit arguments into existential variables, on the
+  shelf, rather than failing.
+
+- Tactic injection has become more powerful (closes bug #4890) and its
+  documentation has been updated.
+
+- New variants of the `first` and `solve` tacticals that do not rely
+  on parsing rules, meant to define tactic notations.
+
+- Added support for side effects hooks in `cbv`, `cbn` and `simpl`.
+  The side effects are provided via a plugin:
+  https://github.com/herbelin/reduction-effects/
+
+- It is now possible to take hint database names as parameters in a
+  Ltac definition or a Tactic Notation.
+
+- New option `Set Ltac Batch Debug` on top of `Set Ltac Debug` for
+  non-interactive Ltac debug output.
+
+Gallina
+
+- Now supporting all kinds of binders, including 'pat, in syntax of record fields.
+
+Vernacular Commands
+
+- Goals context can be printed in a more compact way when `Set
+  Printing Compact Contexts` is activated.
+- Unfocused goals can be printed with the `Set Printing Unfocused`
+  option.
+- `Print` now shows the types of let-bindings.
+- The compatibility options for printing primitive projections
+  (`Set Printing Primitive Projection Parameters` and
+  `Set Printing Primitive Projection Compatibility`) are now off by default.
+- Possibility to unset the printing of notations in a more fine grained
+  fashion than `Unset Printing Notations` is provided without any
+  user-syntax. The goal is that someone creates a plugin to experiment
+  such a user-syntax, to be later integrated in Coq when stabilized.
+- `About` now tells if a reference is a coercion.
+- The deprecated `Save` vernacular and its form `Save Theorem id` to
+  close proofs have been removed from the syntax. Please use `Qed`.
+- `Search` now sorts results by relevance (the relevance metric is a
+  weighted sum of number of distinct symbols and size of the term).
+
+Standard Library
+
+- New file PropExtensionality.v to explicitly work in the axiomatic
+  context of propositional extensionality.
+- New file SetoidChoice.v axiomatically providing choice over setoids,
+  and, consequently, choice of representatives in equivalence classes.
+  Various proof-theoretic characterizations of choice over setoids in
+  file ChoiceFacts.v.
+- New lemmas about iff and about orders on positive and Z.
+- New lemmas on powerRZ.
+- Strengthened statement of JMeq_eq_dep (closes bug #4912).
+- The BigN, BigZ, BigZ libraries are no longer part of the Coq standard
+  library, they are now provided by a separate repository
+  https://github.com/coq/bignums
+  The split has been done just after the Int31 library.
+
+- IZR (Reals) has been changed to produce a compact representation of
+  integers. As a consequence, IZR is no longer convertible to INR and
+  lemmas such as INR_IZR_INZ should be used instead.
+- Real constants are now represented using IZR rather than R0 and R1;
+  this might cause rewriting rules to fail to apply to constants.
+- Added new notation {x & P} for sigT (without a type for x)
+
+Plugins
+
+- The Ssreflect plugin is now distributed with Coq. Its documentation has
+  been integrated as a chapter of the reference manual. This chapter is
+  work in progress so feedback is welcome.
+- The mathematical proof language (also known as declarative mode) was removed.
+- A new command Extraction TestCompile has been introduced, not meant
+  for the general user but instead for Coq's test-suite.
+- The extraction plugin is no longer loaded by default. It must be
+  explicitly loaded with [Require Extraction], which is backwards
+  compatible.
+- The functional induction plugin (which provides the [Function]
+  vernacular) is no longer loaded by default. It must be explicitly
+  loaded with [Require FunInd], which is backwards compatible.
+
+
+Dependencies
+
+- Support for camlp4 has been removed.
+
+Tools
+
+- coq_makefile was completely redesigned to improve its maintainability and
+  the extensibility of generated Makefiles, and to make _CoqProject files
+  more palatable to IDEs.  Overview:
+
+  * _CoqProject files contain only Coq specific data (i.e. the list of
+    files, -R options, ...)
+  * coq_makefile translates _CoqProject to Makefile.conf and copies in the
+    desired location a standard Makefile (that reads Makefile.conf)
+  * Makefile extensions can be implemented in a Makefile.local file (read
+    by the main Makefile) by installing a hook in the extension points
+    provided by the standard Makefile
+
+  The current version contains code for retro compatibility that prints
+  warnings when a deprecated feature is used.  Please upgrade your _CoqProject
+  accordingly.
+
+  * Additionally, coq_makefile-made Makefiles now support experimental timing
+    targets `pretty-timed`, `pretty-timed-before`, `pretty-timed-after`,
+    `print-pretty-timed-diff`, `print-pretty-single-time-diff`,
+    `all.timing.diff`, and the variable `TIMING=1` (or `TIMING=before` or
+    `TIMING=after`); see the documentation for more details.
+
+Build Infrastructure
+
+- Note that 'make world' does not build the bytecode binaries anymore.
+  For that, you can use 'make byte' (and 'make install-byte' afterwards).
+  Warning: native and byte compilations should *not* be mixed in the same
+  instance of 'make -j', otherwise both ocamlc and ocamlopt might race for
+  access to the same .cmi files. In short, use "make -j && make -j byte"
+  instead of "make -j world byte".
+
+Universes
+
+- Cumulative inductive types. see prefixes "Cumulative", "NonCumulative"
+  for inductive definitions and the option "Set Polymorphic Inductive Cumulativity"
+  in the reference manual.
+- New syntax `foo@{_}` to instantiate a polymorphic definition with
+  anonymous universes (can also be used with `Type`).
+
+XML Protocol and internal changes
+
+See dev/doc/changes.txt
+
+Many bugfixes including #1859, #2884, #3613, #3943, #3994,
+#4250, #4709, #4720, #4824, #4844, #4911, #5026, #5233,
+#5275, #5315, #5336, #5360, #5390, #5414, #5417, #5420,
+#5439, #5449, #5475, #5476, #5482, #5501, #5507, #5520,
+#5523, #5524, #5553, #5577, #5578, #5589, #5597, #5598,
+#5607, #5618, #5619, #5620, #5641, #5648, #5651, #5671.
+
+Many bugfixes on OS X and Windows (now the test-suite passes on these
+platforms too).
+
+Many optimizations.
+
+Many documentation improvements.
+
+Details of changes in 8.7+beta2
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Tools
+
+- In CoqIDE, the "Compile Buffer" command takes account of flags in
+  _CoqProject or other project file.
+
+Improvements around some error messages.
+
+Many bug fixes including two important ones:
+
+- Bug #5730: CoqIDE becomes unresponsive on file open.
+- coq_makefile: make sure compile flags for Coq and coq_makefile are in sync
+  (in particular, make sure the `-safe-string` option is used to compile plugins).
+
+Details of changes in 8.7.0
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+OCaml
+
+- Users can pass specific flags to the OCaml optimizing compiler by
+  -using the flambda-opts configure-time option.
+
+  Beware that compiling Coq with a flambda-enabled compiler is
+  experimental and may require large amounts of RAM and CPU, see
+  INSTALL for more details.
+
+Details of changes in 8.7.1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Compatibility with OCaml 4.06.0.
+
+Many bug fixes, documentation improvements, and user message improvements (for
+details see the 8.7.1 milestone at https://github.com/coq/coq/milestone/10?closed=1).
+
+Details of changes in 8.7.2
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Fixed a critical bug in the VM handling of universes (#6677). This bug
+affected all releases since 8.5.
+
+Improved support for building with OCaml 4.06.0 and external num package.
+
+Many other bug fixes, documentation improvements, and user
+message improvements (for details, see the 8.7.2 milestone at
+https://github.com/coq/coq/milestone/11?closed=1).
+
 Version 8.6
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 Coq version 8.6 contains the result of refinements, stabilization of
 8.5’s features and cleanups of the internals of the system. Over the
 year of (now time-based) development, about 450 bugs were resolved and
@@ -502,9 +1232,203 @@ Dénès to put together a |Coq| consortium.
 | Matthieu Sozeau and the |Coq| development team
 |
 
+Details of changes in 8.6beta1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Kernel
+
+- A new, faster state-of-the-art universe constraint checker.
+
+Specification language
+
+- Giving implicit arguments explicitly to a constant with multiple
+  choices of implicit arguments does not break any more insertion of
+  further maximal implicit arguments.
+- Ability to put any pattern in binders, prefixed by quote, e.g.
+  "fun '(a,b) => ...", "λ '(a,(b,c)), ...", "Definition foo '(x,y) := ...".
+  It expands into a "let 'pattern := ..."
+
+Tactics
+
+- Flag "Bracketing Last Introduction Pattern" is now on by default.
+- Flag "Regular Subst Tactic" is now on by default: it respects the
+  initial order of hypothesis, it contracts cycles, it unfolds no
+  local definitions (common source of incompatibilities, fixable by
+  "Unset Regular Subst Tactic").
+- New flag "Refolding Reduction", now disabled by default, which turns
+  on refolding of constants/fixpoints (as in cbn) during the reductions
+  done during type inference and tactic retyping. Can be extremely
+  expensive. When set off, this recovers the 8.4 behaviour of unification
+  and type inference. Potential source of incompatibility with 8.5 developments
+  (the option is set on in Compat/Coq85.v).
+- New flag "Shrink Abstract" that minimalizes proofs generated by the abstract
+  tactical w.r.t. variables appearing in the body of the proof.
+  On by default and deprecated. Minor source of incompatibility
+  for code relying on the precise arguments of abstracted proofs.
+- Serious bugs are fixed in tactic "double induction" (source of
+  incompatibilities as soon as the inductive types have dependencies in
+  the type of their constructors; "double induction" remains however
+  deprecated).
+- In introduction patterns of the form (pat1,...,patn), n should match
+  the exact number of hypotheses introduced (except for local definitions
+  for which pattern can be omitted, as in regular pattern-matching).
+- Tactic scopes in Ltac like constr: and ltac: now require parentheses around
+  their argument.
+- Every generic argument type declares a tactic scope of the form "name:(...)"
+  where name is the name of the argument. This generalizes the constr: and ltac:
+  instances.
+- When in strict mode (i.e. in a Ltac definition), if the "intro" tactic is
+  given a free identifier, it is not bound in subsequent tactics anymore.
+  In order to introduce a binding, use e.g. the "fresh" primitive instead
+  (potential source of incompatibilities).
+- New tactics is_ind, is_const, is_proj, is_constructor for use in Ltac.
+- New goal selectors.  Sets of goals can be selected by listing integers
+  ranges. Example: "1,4-7,24: tac" focuses "tac" on goals 1,4,5,6,7,24.
+- For uniformity with "destruct"/"induction" and for a more natural
+  behavior, "injection" can now work in place by activating option
+  "Structural Injection". In this case, hypotheses are also put in the
+  context in the natural left-to-right order and the hypothesis on
+  which injection applies is cleared.
+- Tactic "contradiction" (hence "easy") now also solve goals with
+  hypotheses of the form "~True" or "t<>t" (possible source of
+  incompatibilities because of more successes in automation, but
+  generally a more intuitive strategy).
+- Option "Injection On Proofs" was renamed "Keep Proof Equalities". When
+  enabled, injection and inversion do not drop equalities between objects
+  in Prop. Still disabled by default.
+- New tactics "notypeclasses refine" and "simple notypeclasses refine" that
+  disallow typeclass resolution when typechecking their argument, for use
+  in typeclass hints.
+- Integration of LtacProf, a profiler for Ltac.
+- Reduction tactics now accept more fine-grained flags: iota is now a shorthand
+  for the new flags match, fix and cofix.
+- The ssreflect subterm selection algorithm is now accessible to tactic writers
+  through the ssrmatching plugin.
+- When used as an argument of an ltac function, "auto" without "with"
+  nor "using" clause now correctly uses only the core hint database by
+  default.
+
+Hints
+
+- Revised the syntax of [Hint Cut] to follow standard notation for regexps.
+- Hint Mode now accepts "!" which means that the mode matches only if the
+  argument's head is not an evar (it goes under applications, casts, and
+  scrutinees of matches and projections).
+- Hints can now take an optional user-given pattern, used only by
+  [typeclasses eauto] with the [Filtered Unification] option on.
+
+Typeclasses
+
+- Many new options and new engine based on the proof monad. The
+  [typeclasses eauto] tactic is now a multi-goal, multi-success tactic.
+  See reference manual for more information. It is planned to
+  replace auto and eauto in the following version. The 8.5 resolution
+  engine is still available to help solve compatibility issues.
+
+Program
+
+- The "Shrink Obligations" flag now applies to all obligations, not only
+  those solved by the automatic tactic.
+- "Shrink Obligations" is on by default and deprecated. Minor source of
+  incompatibility for code relying on the precise arguments of
+  obligations.
+
+Notations
+
+- "Bind Scope" can once again bind "Funclass" and "Sortclass".
+
+General infrastructure
+
+- New configurable warning system which can be controlled with the vernacular
+  command "Set Warnings", or, under coqc/coqtop, with the flag "-w". In
+  particular, the default is now that warnings are printed by coqc.
+- In asynchronous mode, Coq is now capable of recovering from errors and
+  continue processing the document.
+
+Tools
+
+- coqc accepts a -o option to specify the output file name
+- coqtop accepts --print-version to print Coq and OCaml versions in
+  easy to parse format
+- Setting [Printing Dependent Evars Line] can be unset to disable the
+  computation associated with printing the "dependent evars: " line in
+  -emacs mode
+- Removed the -verbose-compat-notations flag and the corresponding Set
+  Verbose Compat vernacular, since these warnings can now be silenced or
+  turned into errors using "-w".
+
+XML protocol
+
+- message format has changed, see dev/doc/changes.txt for more details.
+
+Many bug fixes, minor changes and documentation improvements are not mentioned
+here.
+
+Details of changes in 8.6
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Kernel
+
+- Fixed critical bug #5248 in VM long multiplication on 32-bit
+  architectures. Was there only since 8.6beta1, so no stable release impacted.
+
+Other bug fixes in universes, type class shelving,...
+
+Details of changes in 8.6.1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+- Fix #5380: Default colors for CoqIDE are actually applied.
+- Fix plugin warnings
+- Document named evars (including Show ident)
+- Fix Bug #5574, document function scope
+- Adding a test case as requested in bug 5205.
+- Fix Bug #5568, no dup notation warnings on repeated module imports
+- Fix documentation of Typeclasses eauto :=
+- Refactor documentation of records.
+- Protecting from warnings while compiling 8.6
+- Fixing an inconsistency between configure and configure.ml
+- Add test-suite checks for coqchk with constraints
+- Fix bug #5019 (looping zify on dependent types)
+- Fix bug 5550: "typeclasses eauto with" does not work with section variables.
+- Bug 5546, qualify datatype constructors when needed in Show Match
+- Bug #5535, test for Show with -emacs
+- Fix bug #5486, don't reverse ids in tuples
+- Fixing #5522 (anomaly with free vars of pat)
+- Fix bug #5526, don't check for nonlinearity in notation if printing only
+- Fix bug #5255
+- Fix bug #3659: -time should understand multibyte encodings.
+- FIx bug #5300: Anomaly: Uncaught exception Not_found" in "Print Assumptions".
+- Fix outdated description in RefMan.
+- Repairing `Set Rewriting Schemes`
+- Fixing #5487 (v8.5 regression on ltac-matching expressions with evars).
+- Fix description of command-line arguments for Add (Rec) LoadPath
+- Fix bug #5377: @? patterns broken.
+- add XML protocol doc
+- Fix anomaly when doing [all:Check _.] during a proof.
+- Correction of bug #4306
+- Fix #5435: [Eval native_compute in] raises anomaly.
+- Instances should obey universe binders even when defined by tactics.
+- Intern names bound in match patterns
+- funind: Ignore missing info for current function
+- Do not typecheck twice the type of opaque constants.
+- show unused intro pattern warning
+- [future] Be eager when "chaining" already resolved future values.
+- Opaque side effects
+- Fix #5132: coq_makefile generates incorrect install goal
+- Run non-tactic comands without resilient_command
+- Univs: fix bug #5365, generation of u+k <= v constraints
+- make ``emit`` tail recursive
+- Don't require printing-only notation to be productive
+- Fix the way setoid_rewrite handles bindings.
+- Fix for bug 5244 - set printing width ignored when given enough space
+- Fix bug 4969, autoapply was not tagging shelved subgoals correctly
+
 Version 8.5
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 Coq version 8.5 contains the result of five specific long-term projects:
 
 -  A new asynchronous evaluation and compilation mode by Enrico Tassi
@@ -656,9 +1580,787 @@ Tankink. Maxime Dénès coordinated the release process.
 | Hugo Herbelin, Matthieu Sozeau and the |Coq| development team
 |
 
+Details of changes in 8.5beta1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Logic
+
+- Primitive projections for records allow for a compact representation
+  of projections, without parameters and avoid the behavior of defined
+  projections that can unfold to a case expression. To turn the use of
+  native projections on, use [Set Primitive Projections]. Record,
+  Class and Structure types defined while this option is set will be
+  defined with primitive projections instead of the usual encoding as
+  a case expression. For compatibility, when p is a primitive
+  projection, @p can be used to refer to the projection with explicit
+  parameters, i.e. [@p] is definitionally equal to [λ params r. r.(p)].
+  Records with primitive projections have eta-conversion, the
+  canonical form being [mkR pars (p1 t) ... (pn t)].
+- New universe polymorphism (see reference manual)
+- New option -type-in-type to collapse the universe hierarchy (this makes the
+  logic inconsistent).
+- The guard condition for fixpoints is now a bit stricter. Propagation
+  of subterm value through pattern matching is restricted according to
+  the return predicate. Restores compatibility of Coq's logic with the
+  propositional extensionality axiom. May create incompatibilities in
+  recursive programs heavily using dependent types.
+- Trivial inductive types are no longer defined in Type but in Prop, which
+  leads to a non-dependent induction principle being generated in place of
+  the dependent one. To recover the old behavior, explicitly define your
+  inductive types in Set.
+
+Vernacular commands
+
+- A command "Variant" allows to define non-recursive variant types.
+- The command "Record foo ..." does not generate induction principles
+  (foo_rect, foo_rec, foo_ind) anymore by default (feature wish
+  #2693). The command "Variant foo ..." does not either. A flag
+  "Set/Unset Nonrecursive Elimination Schemes" allows changing this.
+  The tactic "induction" on a "Record" or a "Variant" is now actually
+  doing "destruct".
+- The "Open Scope" command can now be given also a delimiter (e.g. Z).
+- The "Definition" command now allows the "Local" modifier, allowing
+  for non-importable definitions. The same goes for "Axiom" and "Parameter".
+- Section-specific commands such as "Let" (resp. "Variable", "Hypothesis") used
+  out of a section now behave like the corresponding "Local" command, i.e.
+  "Local Definition" (resp. "Local Parameter", "Local Axiom"). (potential source
+  of rare incompatibilities).
+- The "Let" command can now define local (co)fixpoints.
+- Command "Search" has been renamed into "SearchHead". The command
+  name "Search" now behaves like former "SearchAbout". The latter name
+  is deprecated.
+- "Search", "About", "SearchHead", "SearchRewrite" and "SearchPattern"
+  now search for hypothesis (of the current goal by default) first.
+  They now also support the goal selector prefix to specify another
+  goal to search: e.g. "n:Search id". This is also true for
+  SearchAbout although it is deprecated.
+- The coq/user-contrib directory and the XDG directories are no longer
+  recursively added to the load path, so files from installed libraries
+  now need to be fully qualified for the "Require" command to find them.
+  The tools/update-require script can be used to convert a development.
+- A new Print Strategies command allows visualizing the opacity status
+  of the whole engine.
+- The "Locate" command now searches through all sorts of qualified namespaces of
+  Coq: terms, modules, tactics, etc. The old behavior of the command can be
+  retrieved using the "Locate Term" command.
+- New "Derive" command to help writing program by derivation.
+- New "Refine Instance Mode" option that allows to deactivate the generation of
+  obligations in incomplete typeclass instances, raising an error instead.
+- "Collection" command to name sets of section hypotheses.  Named collections
+  can be used in the syntax of "Proof using" to assert which section variables
+  are used in a proof.
+- The "Optimize Proof" command can be placed in the middle of a proof to
+  force the compaction of the data structure used to represent the ongoing
+  proof (evar map). This may result in a lower memory footprint and speed up
+  the execution of the following tactics.
+- "Optimize Heap" command to tell the OCaml runtime to perform a major
+  garbage collection step and heap compaction.
+- ``Instance`` no longer treats the ``{|...|}`` syntax specially; it handles it
+  in the same way as other commands, e.g. "Definition". Use the ``{...}``
+  syntax (no pipe symbols) to recover the old behavior.
+
+Specification Language
+
+- Slight changes in unification error messages.
+- Added a syntax $(...)$ that allows putting tactics in terms (may
+  break user notations using "$(", fixable by inserting a space or
+  rewriting the notation).
+- Constructors in pattern-matching patterns now respect the same rules
+  regarding implicit arguments as in applicative position. The old
+  behavior can be recovered by the command "Set Asymmetric
+  Patterns". As a side effect, notations for constructors explicitly
+  mentioning non-implicit parameters can now be used in patterns.
+  Considering that the pattern language is already rich enough, binding
+  local definitions is however now forbidden in patterns (source of
+  incompatibilities for local definitions that delta-reduce to a constructor).
+- Type inference algorithm now granting opacity of constants. This might also
+  affect behavior of tactics (source of incompatibilities, solvable by
+  re-declaring transparent constants which were set opaque).
+- Existential variables are now referred to by an identifier and the
+  relevant part of their instance is displayed by default. They can be
+  reparsed. The naming policy is yet unstable and subject to changes
+  in future releases.
+
+Tactics
+
+- New tactic engine allowing dependent subgoals, fully backtracking
+  (also known as multiple success) tactics, as well as tactics which
+  can consider multiple goals together. In the new tactic engine,
+  instantiation information of existential variables is always
+  propagated to tactics, removing the need to manually use the
+  "instantiate" tactics to mark propagation points.
+
+  * New tactical (a+b) inserts a backtracking point. When (a+b);c fails
+    during the execution of c, it can backtrack and try b instead of a.
+  * New tactical (once a) removes all the backtracking points from a
+    (i.e. it selects the first success of a).
+  * Tactic "constructor" is now fully backtracking. In case of
+    incompatibilities (e.g. combinatoric explosion), the former
+    behavior of "constructor" can be retrieved by using instead
+    "[> once constructor ..]". Thanks to backtracking, undocumented
+    "constructor <tac>" syntax is now equivalent to
+    "[> once (constructor; tac) ..]".
+  * New "multimatch" variant of "match" tactic which backtracks to
+    new branches in case of a later failure. The "match" tactic is
+    equivalent to "once multimatch".
+  * New selector "all:" such that "all:tac" applies tactic "tac" to
+    all the focused goals, instead of just the first one as is the
+    default.
+  * A corresponding new option Set Default Goal Selector "all" makes
+    the tactics in scripts be applied to all the focused goal by default
+  * New selector "par:" such that "par:tac" applies the (terminating)
+    tactic "tac" to all the focused goal in parallel. The number of worker
+    can be selected with -async-proofs-tac-j and also limited using the
+    coqworkmgr utility.
+  * New tactics "revgoals", "cycle" and "swap" to reorder goals.
+  * The semantics of recursive tactics (introduced with "Ltac t := ..."
+    or "let rec t := ... in ...") changed slightly as t is now
+    applied to every goal, not each goal independently. In particular
+    it may be applied when no goals are left. This may cause tactics
+    such as "let rec t := constructor;t" to loop indefinitely. The
+    simple fix is to rewrite the recursive calls as follows:
+    "let rec t := constructor;[t..]" which recovers the earlier behavior
+    (source of rare incompatibilities).
+  * New tactic language feature "numgoals" to count number of goals. It is
+    accompanied by a "guard" tactic which fails if a Boolean test over
+    integers does not pass.
+  * New tactical "[> ... ]" to apply tactics to individual goals.
+  * New tactic "gfail" which works like "fail" except it will also
+    fail if every goal has been solved.
+  * The refine tactic is changed not to use an ad hoc typing algorithm
+    to generate subgoals. It also uses the dependent subgoal feature
+    to generate goals to materialize every existential variable which
+    is introduced by the refinement (source of incompatibilities).
+  * A tactic shelve is introduced to manage the subgoals which may be
+    solved by unification: shelve removes every goal it is applied to
+    from focus. These goals can later be called back into focus by the
+    Unshelve command.
+  * A variant shelve_unifiable only removes those goals which appear
+    as existential variables in other goals. To emulate the old
+    refine, use "refine c;shelve_unifiable". This can still cause
+    incompatibilities in rare occasions.
+  * New "give_up" tactic to skip over a goal.  A proof containing
+    given up goals cannot be closed with "Qed", but only with "Admitted".
+
+- The implementation of the admit tactic has changed: no axiom is
+  generated for the admitted sub proof. "admit" is now an alias for
+  "give_up".  Code relying on this specific behavior of "admit"
+  can be made to work by:
+
+  * Adding an "Axiom" for each admitted subproof.
+  * Adding a single "Axiom proof_admitted : False." and the Ltac definition
+    "Ltac admit := case proof_admitted.".
+
+- Matching using "lazymatch" was fundamentally modified. It now behaves
+  like "match" (immediate execution of the matching branch) but without
+  the backtracking mechanism in case of failure.
+
+- New "tryif t then u else v" tactical which executes "u" in case of success
+  of "t" and "v" in case of failure.
+
+- New conversion tactic "native_compute": evaluates the goal (or an hypothesis)
+  with a call-by-value strategy, using the OCaml native compiler. Useful on
+  very intensive computations.
+
+- New "cbn" tactic, a well-behaved simpl.
+
+- Repeated identical calls to omega should now produce identical proof terms.
+
+- Tactics btauto, a reflexive Boolean tautology solver.
+
+- Tactic "tauto" was exceptionally able to destruct other connectives
+  than the binary connectives "and", "or", "prod", "sum", "iff". This
+  non-uniform behavior has been fixed (bug #2680) and tauto is
+  slightly weaker (possible source of incompatibilities). On the
+  opposite side, new tactic "dtauto" is able to destruct any
+  record-like inductive types, superseding the old version of "tauto".
+
+- Similarly, "intuition" has been made more uniform and, where it now
+  fails, "dintuition" can be used (possible source of incompatibilities).
+
+- New option "Unset Intuition Negation Unfolding" for deactivating automatic
+  unfolding of "not" in intuition.
+
+- Tactic notations can now be defined locally to a module (use "Local" prefix).
+
+- Tactic "red" now reduces head beta-iota redexes (potential source of
+  rare incompatibilities).
+
+- Tactic "hnf" now reduces inner beta-iota redexes
+  (potential source of rare incompatibilities).
+
+- Tactic "intro H" now reduces beta-iota redexes if these hide a product
+  (potential source of rare incompatibilities).
+
+- In Ltac matching on patterns of the form "_ pat1 ... patn" now
+  behaves like if matching on "?X pat1 ... patn", i.e. accepting "_"
+  to be instantiated by an applicative term (experimental at this
+  stage, potential source of incompatibilities).
+
+- In Ltac matching on goal, types of hypotheses are now interpreted in
+  the %type scope (possible source of incompatibilities).
+
+- "change ... in ..." and "simpl ... in ..." now properly consider nested
+  occurrences (possible source of incompatibilities since this alters
+  the numbering of occurrences), but do not support nested occurrences.
+
+- Tactics simpl, vm_compute and native_compute can be given a notation string
+  to a constant as argument.
+
+- When given a reference as argument, simpl, vm_compute and
+  native_compute now strictly interpret it as the head of a pattern
+  starting with this reference.
+
+- The "change p with c" tactic semantics changed, now type-checking
+  "c" at each matching occurrence "t" of the pattern "p", and
+  converting "t" with "c".
+
+- Now "appcontext" and "context" behave the same. The old buggy behavior of
+  "context" can be retrieved at parse time by setting the
+  "Tactic Compat Context" flag (possible source of incompatibilities).
+
+- New introduction pattern p/c which applies lemma c on the fly on the
+  hypothesis under consideration before continuing with introduction pattern p.
+
+- New introduction pattern [= x1 .. xn] applies "injection as [x1 .. xn]"
+  on the fly if injection is applicable to the hypothesis under consideration
+  (idea borrowed from Georges Gonthier). Introduction pattern [=] applies
+  "discriminate" if a discriminable equality.
+
+- New introduction patterns * and ** to respectively introduce all forthcoming
+  dependent variables and all variables/hypotheses dependent or not.
+
+- Tactic "injection c as ipats" now clears c if c refers to an
+  hypothesis and moves the resulting equations in the hypotheses
+  independently of the number of ipats, which has itself to be less
+  than the number of new hypotheses (possible source of incompatibilities;
+  former behavior obtainable by "Unset Injection L2R Pattern Order").
+
+- Tactic "injection" now automatically simplifies subgoals
+  "existT n p = existT n p'" into "p = p'" when "n" is in an inductive type for
+  which a decidable equality scheme has been generated with "Scheme Equality"
+  (possible source of incompatibilities).
+
+- New tactic "rewrite_strat" for generalized rewriting with user-defined
+  strategies, subsuming autorewrite.
+
+- Injection can now also deduce equality of arguments of sort Prop, by using
+  the option "Set Injection On Proofs" (disabled by default). Also improved the
+  error messages.
+
+- Tactic "subst id" now supports id occurring in dependent local definitions.
+
+- Bugs fixed about intro-pattern "*" might lead to some rare incompatibilities.
+
+- New tactical "time" to display time spent executing its argument.
+
+- Tactics referring or using a constant dependent in a section variable which
+  has been cleared or renamed in the current goal context now fail
+  (possible source of incompatibilities solvable by avoiding clearing
+  the relevant hypotheses).
+
+- New construct "uconstr:c" and "type_term c" to build untyped terms.
+
+- Binders in terms defined in Ltac (either "constr" or "uconstr") can
+  now take their names from identifiers defined in Ltac. As a
+  consequence, a name cannot be used in a binder "constr:(fun x =>
+  ...)" if an Ltac variable of that name already exists and does not
+  contain an identifier. Source of occasional incompatibilities.
+
+- The "refine" tactic now accepts untyped terms built with "uconstr"
+  so that terms with holes can be constructed piecewise in Ltac.
+
+- New bullets --, ++, **, ---, +++, ***, ... made available.
+
+- More informative messages when wrong bullet is used.
+
+- Bullet suggestion when a subgoal is solved.
+
+- New tactic "enough", symmetric to "assert", but with subgoals
+  swapped, as a more friendly replacement of "cut".
+
+- In destruct/induction, experimental modifier "!" prefixing the
+  hypothesis name to tell not erasing the hypothesis.
+
+- Bug fixes in "inversion as" may occasionally lead to incompatibilities.
+
+- Behavior of introduction patterns -> and <- made more uniform
+  (hypothesis is cleared, rewrite in hypotheses and conclusion and
+  erasing the variable when rewriting a variable).
+
+- New experimental option "Set Standard Proposition Elimination Names"
+  so that case analysis or induction on schemes in Type containing
+  propositions now produces "H"-based names.
+
+- Tactics from plugins are now active only when the corresponding module
+  is imported (source of incompatibilities, solvable by adding an "Import";
+  in the particular case of Omega, use "Require Import OmegaTactic").
+
+- Semantics of destruct/induction has been made more regular in some
+  edge cases, possibly leading to incompatibilities:
+
+  + new goals are now opened when the term does not match a subterm of
+    the goal and has unresolved holes, while in 8.4 these holes were
+    turned into existential variables
+  + when no "at" option is given, the historical semantics which
+    selects all subterms syntactically identical to the first subterm
+    matching the given pattern is used
+  + non-dependent destruct/induction on an hypothesis with premises in
+    an inductive type with indices is fixed
+  + residual local definitions are now correctly removed.
+
+- The rename tactic may now replace variables in parallel.
+
+- A new "Info" command replaces the "info" tactical discontinued in
+  v8.4. It still gives informative results in many cases.
+
+- The "info_auto" tactic is known to be broken and does not print a
+  trace anymore. Use "Info 1 auto" instead. The same goes for
+  "info_trivial". On the other hand "info_eauto" still works fine,
+  while "Info 1 eauto" prints a trivial trace.
+
+- When using a lemma of the prototypical form "forall A, {a:A & P a}",
+  "apply" and "apply in" do not instantiate anymore "A" with the
+  current goal and use "a" as the proof, as they were sometimes doing,
+  now considering that it is a too powerful decision.
+
+Program
+
+- "Solve Obligations using" changed to "Solve Obligations with",
+  consistent with "Proof with".
+- Program Lemma, Definition now respect automatic introduction.
+- Program Lemma, Definition, etc.. now interpret "->" like Lemma and
+  Definition as a non-dependent arrow (potential source of
+  incompatibility).
+- Add/document "Set Hide Obligations" (to hide obligations in the final
+  term inside an implicit argument) and "Set Shrink Obligations" (to
+  minimize dependencies of obligations defined by tactics).
+
+Notations
+
+- The syntax "x -> y" is now declared at level 99. In particular, it has
+  now a lower priority than "<->": "A -> B <-> C" is now "A -> (B <-> C)"
+  (possible source of incompatibilities)
+- Notations accept term-providing tactics using the $(...)$ syntax.
+- "Bind Scope" can no longer bind "Funclass" and "Sortclass".
+- A notation can be given a (compat "8.x") annotation, making it behave
+  like a "only parsing" notation, but the annotation may lead to eventually
+  issue warnings or errors in further versions when this notation is used.
+- More systematic insertion of spaces as a default for printing
+  notations ("format" still available to override the default).
+- In notations, a level modifier referring to a non-existent variable is
+  now considered an error rather than silently ignored.
+
+Tools
+
+- Option -I now only adds directories to the ml path.
+- Option -Q behaves as -R, except that the logical path of any loaded file has
+  to be fully qualified.
+- Option -R no longer adds recursively to the ml path; only the root
+  directory is added. (Behavior with respect to the load path is
+  unchanged.)
+- Option -nois prevents coq/theories and coq/plugins to be recursively
+  added to the load path. (Same behavior as with coq/user-contrib.)
+- coqdep accepts a -dumpgraph option generating a dot file.
+- Makefiles generated through coq_makefile have three new targets "quick"
+  "checkproofs" and "vio2vo", allowing respectively to asynchronously compile
+  the files without playing the proof scripts, asynchronously checking
+  that the quickly generated proofs are correct and generating the object
+  files from the quickly generated proofs.
+- The XML plugin was discontinued and removed from the source.
+- A new utility called coqworkmgr can be used to limit the number of
+  concurrent workers started by independent processes, like make and CoqIDE.
+  This is of interest for users of the par: goal selector.
+
+Interfaces
+
+- CoqIDE supports asynchronous edition of the document, ongoing tasks and
+  errors are reported in the bottom right window.  The number of workers
+  taking care of processing proofs can be selected with -async-proofs-j.
+- CoqIDE highlights in yellow "unsafe" commands such as axiom
+  declarations, and tactics like "give_up".
+- CoqIDE supports Proof General like key bindings;
+  to activate the PG mode go to Edit -> Preferences -> Editor.
+  For the documentation see Help -> Help for PG mode.
+- CoqIDE automatically retracts the locked area when one edits the
+  locked text.
+- CoqIDE search and replace got regular expressions power. See the
+  documentation of OCaml's Str module for the supported syntax.
+- Many CoqIDE windows, including the query one, are now detachable to
+  improve usability on multi screen work stations.
+- Coqtop/coqc outputs highlighted syntax. Colors can be configured thanks
+  to the COQ_COLORS environment variable, and their current state can
+  be displayed with the -list-tags command line option.
+- Third party user interfaces can install their main loop in $COQLIB/toploop
+  and call coqtop with the -toploop flag to select it.
+
+Internal Infrastructure
+
+- Many reorganizations in the ocaml source files. For instance,
+  many internal a.s.t. of Coq are now placed in mli files in
+  a new directory intf/, for instance constrexpr.mli or glob_term.mli.
+  More details in dev/doc/changes.
+
+- The file states/initial.coq does not exist anymore. Instead, coqtop
+  initially does a "Require" of Prelude.vo (or nothing when given
+  the options -noinit or -nois).
+
+- The format of vo files has slightly changed: cf final comments in
+  checker/cic.mli.
+
+- The build system does not produce anymore programs named coqtop.opt
+  and a symbolic link to coqtop. Instead, coqtop is now directly
+  an executable compiled with the best OCaml compiler available.
+  The bytecode program coqtop.byte is still produced. Same for other
+  utilities.
+
+- Some options of the ./configure script slightly changed:
+
+  * The -coqrunbyteflags and its blank-separated argument is replaced
+    by option -vmbyteflags which expects a comma-separated argument.
+  * The -coqtoolsbyteflags option is discontinued, see -no-custom instead.
+
+Miscellaneous
+
+- ML plugins now require a "DECLARE PLUGIN \"foo\"" statement. The "foo" name
+  must be exactly the name of the ML module that will be loaded through a
+  "Declare ML \"foo\"" command.
+
+Details of changes in 8.5beta2
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Logic
+
+- The VM now supports inductive types with up to 8388851 non-constant
+  constructors and up to 8388607 constant ones.
+
+Specification language
+
+- Syntax "$(tactic)$" changed to "ltac: tactic".
+
+Tactics
+
+- A script using the admit tactic can no longer be concluded by either
+  Qed or Defined. In the first case, Admitted can be used instead. In
+  the second case, a subproof should be used.
+- The easy tactic and the now tactical now have a more predictable
+  behavior, but they might now discharge some previously unsolved goals.
+
+Extraction
+
+- Definitions extracted to Haskell GHC should no longer randomly
+  segfault when some Coq types cannot be represented by Haskell types.
+- Definitions can now be extracted to Json for post-processing.
+
+Tools
+
+- Option -I -as has been removed, and option -R -as has been
+  deprecated. In both cases, option -R can be used instead.
+- coq_makefile now generates double-colon rules for rules such as clean.
+
+API
+
+- The interface of [change] has changed to take a [change_arg], which
+  can be built from a [constr] using [make_change_arg].
+
+Details of changes in 8.5beta3
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Vernacular commands
+
+- New command "Redirect" to redirect the output of a command to a file.
+- New command "Undelimit Scope" to remove the delimiter of a scope.
+- New option "Strict Universe Declaration", set by default. It enforces the
+  declaration of all polymorphic universes appearing in a definition when
+  introducing it.
+- New command "Show id" to show goal named id.
+- Option "Virtual Machine" removed.
+
+Tactics
+
+- New flag "Regular Subst Tactic" which fixes "subst" in situations where
+  it failed to substitute all substitutable equations or failed to simplify
+  cycles, or accidentally unfolded local definitions (flag is off by default).
+- New flag "Loose Hint Behavior" to handle hints loaded but not imported in a
+  special way. It accepts three distinct flags:
+  * "Lax", which is the default one, sets the old behavior, i.e. a non-imported
+  hint behaves the same as an imported one.
+  * "Warn" outputs a warning when a non-imported hint is used. Note that this is
+  an over-approximation, because a hint may be triggered by an eauto run that
+  will eventually fail and backtrack.
+  * "Strict" changes the behavior of an unloaded hint to the one of the fail
+  tactic, allowing to emulate the hopefully future import-scoped hint mechanism.
+- New compatibility flag "Universal Lemma Under Conjunction" which
+  let tactics working under conjunctions apply sublemmas of the form
+  "forall A, ... -> A".
+- New compatibility flag "Bracketing Last Introduction Pattern" which can be
+  set so that the last disjunctive-conjunctive introduction pattern given to
+  "intros" automatically complete the introduction of its subcomponents, as the
+  the disjunctive-conjunctive introduction patterns in non-terminal position
+  already do.
+- New flag "Shrink Abstract" that minimalizes proofs generated by the abstract
+  tactical w.r.t. variables appearing in the body of the proof.
+
+Program
+
+- The "Shrink Obligations" flag now applies to all obligations, not only those
+  solved by the automatic tactic.
+- Importing Program no longer overrides the "exists" tactic (potential source
+  of incompatibilities).
+- Hints costs are now correctly taken into account (potential source of
+  incompatibilities).
+- Documented the Hint Cut command that allows control of the
+  proof-search during typeclass resolution (see reference manual).
+
+API
+
+- Some functions from pretyping/typing.ml and their derivatives were potential
+  source of evarmap leaks, as they dropped their resulting evarmap. The
+  situation was clarified by renaming them according to a ``unsafe_*`` scheme. Their
+  sound variant is likewise renamed to their old name. The following renamings
+  were made.
+
+  * ``Typing.type_of`` -> ``unsafe_type_of``
+  * ``Typing.e_type_of`` -> ``type_of``
+  * A new ``e_type_of`` function that matches the ``e_`` prefix policy
+  * ``Tacmach.pf_type_of`` -> ``pf_unsafe_type_of``
+  * A new safe ``pf_type_of`` function.
+
+  All uses of ``unsafe_*`` functions should be eventually eliminated.
+
+Tools
+
+- Added an option -w to control the output of coqtop warnings.
+- Configure now takes an optional -native-compiler (yes|no) flag replacing
+  -no-native-compiler. The new flag is set to no by default under Windows.
+- Flag -no-native-compiler was removed and became the default for coqc. If
+  precompilation of files for native conversion test is desired, use
+  -native-compiler.
+- The -compile command-line option now takes the full path of the considered
+  file, including the ".v" extension, and outputs a warning if such an extension
+  is lacking.
+- The -require and -load-vernac-object command-line options now take a logical
+  path of a given library rather than a physical path, thus they behave like
+  Require [Import] path.
+- The -vm command-line option has been removed.
+
+Standard Library
+
+ - There is now a Coq.Compat.Coq84 library, which sets the various compatibility
+   options and does a few redefinitions to make Coq behave more like Coq v8.4.
+   The standard way of putting Coq in v8.4 compatibility mode is to pass the command
+   line flags "-require Coq.Compat.Coq84 -compat 8.4".
+
+Details of changes in 8.5
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Tools
+
+- Flag "-compat 8.4" now loads Coq.Compat.Coq84. The standard way of
+  putting Coq in v8.4 compatibility mode is to pass the command line flag
+  "-compat 8.4". It can be followed by "-require Coq.Compat.AdmitAxiom"
+  if the 8.4 behavior of admit is needed, in which case it uses an axiom.
+
+Specification language
+
+- Syntax "$(tactic)$" changed to "ltac:(tactic)".
+
+Tactics
+
+- Syntax "destruct !hyp" changed to "destruct (hyp)", and similarly
+  for induction (rare source of incompatibilities easily solvable by
+  removing parentheses around "hyp" when not for the purpose of keeping
+  the hypothesis).
+- Syntax "p/c" for on-the-fly application of a lemma c before
+  introducing along pattern p changed to p%c1..%cn. The feature and
+  syntax are in experimental stage.
+- "Proof using" does not clear unused section variables.
+- Tactic "refine" has been changed back to the 8.4 behavior of shelving subgoals
+  that occur in other subgoals. The "refine" tactic of 8.5beta3 has been
+  renamed "simple refine"; it does not shelve any subgoal.
+- New tactical "unshelve tac" which grab existential variables put on
+  the tactic shelve by the execution of "tac".
+
+Details of changes in 8.5pl1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Critical bugfix
+
+- The subterm relation for the guard condition was incorrectly defined on
+  primitive projections (#4588)
+
+Plugin development tools
+
+- add a .merlin target to the makefile
+
+Various performance improvements (time, space used by .vo files)
+
+Other bugfixes
+
+- Fix order of arguments to Big.compare_case in ExtrOcamlZBigInt.v
+- Added compatibility coercions from Specif.v which were present in Coq 8.4.
+- Fixing a source of inefficiency and an artificial dependency in the printer in the congruence tactic.
+- Allow to unset the refinement mode of Instance in ML
+- Fixing an incorrect use of prod_appvect on a term which was not a product in setoid_rewrite.
+- Add -compat 8.4 econstructor tactics, and tests
+- Add compatibility Nonrecursive Elimination Schemes
+- Fixing the "No applicable tactic" non informative error message regression on apply.
+- Univs: fix get_current_context (bug #4603, part I)
+- Fix a bug in Program coercion code
+- Fix handling of arity of definitional classes.
+- #4630: Some tactics are 20x slower in 8.5 than 8.4.
+- #4627: records with no declared arity can be template polymorphic.
+- #4623: set tactic too weak with universes (regression)
+- Fix incorrect behavior of CS resolution
+- #4591: Uncaught exception in directory browsing.
+- CoqIDE is more resilient to initialization errors.
+- #4614: "Fully check the document" is uninterruptable.
+- Try eta-expansion of records only on non-recursive ones
+- Fix bug when a sort is ascribed to a Record
+- Primitive projections: protect kernel from erroneous definitions.
+- Fixed bug #4533 with previous Keyed Unification commit
+- Win: kill unreliable hence do not waitpid after kill -9 (Close #4369)
+- Fix strategy of Keyed Unification
+- #4608: Anomaly "output_value: abstract value (outside heap)".
+- #4607: do not read native code files if native compiler was disabled.
+- #4105: poor escaping in the protocol between CoqIDE and coqtop.
+- #4596: [rewrite] broke in the past few weeks.
+- #4533 (partial): respect declared global transparency of projections in unification.ml
+- #4544: Backtrack on using full betaiota reduction during keyed unification.
+- #4540: CoqIDE bottom progress bar does not update.
+- Fix regression from 8.4 in reflexivity
+- #4580: [Set Refine Instance Mode] also used for Program Instance.
+- #4582: cannot override notation [ x ]. MAY CREATE INCOMPATIBILITIES, see #4683.
+- STM: Print/Extraction have to be skipped if -quick
+- #4542: CoqIDE: STOP button also stops workers
+- STM: classify some variants of Instance as regular `` `Fork `` nodes.
+- #4574: Anomaly: Uncaught exception Invalid_argument("splay_arity").
+- Do not give a name to anonymous evars anymore. See bug #4547.
+- STM: always stock in vio files the first node (state) of a proof
+- STM: not delegate proofs that contain Vernac(Module|Require|Import), #4530
+- Don't fail fatally if PATH is not set.
+- #4537: Coq 8.5 is slower in typeclass resolution.
+- #4522: Incorrect "Warning..." on windows.
+- #4373: coqdep does not know about .vio files.
+- #3826: "Incompatible module types" is uninformative.
+- #4495: Failed assertion in metasyntax.ml.
+- #4511: evar tactic can create non-typed evars.
+- #4503: mixing universe polymorphic and monomorphic variables and definitions in sections is unsupported.
+- #4519: oops, global shadowed local universe level bindings.
+- #4506: Anomaly: File "pretyping/indrec.ml", line 169, characters 14-20: Assertion failed.
+- #4548: Coqide crashes when going back one command
+
+Details of changes in 8.5pl2
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Critical bugfix
+
+- Checksums of .vo files dependencies were not correctly checked.
+- Unicode-to-ASCII translation was not injective, leading in a soundness bug in
+  the native compiler.
+
+Other bugfixes
+
+- #4097: more efficient occur-check in presence of primitive projections
+- #4398: type_scope used consistently in "match goal".
+- #4450: eauto does not work with polymorphic lemmas
+- #4677: fix alpha-conversion in notations needing eta-expansion.
+- Fully preserve initial order of hypotheses in "Regular Subst Tactic" mode.
+- #4644: a regression in unification.
+- #4725: Function (Error: Conversion test raised an anomaly) and Program
+  (Error: Cannot infer this placeholder of type)
+- #4747: Problem building Coq 8.5pl1 with OCaml 4.03.0: Fatal warnings
+- #4752: CoqIDE crash on files not ended by ".v".
+- #4777: printing inefficiency with implicit arguments
+- #4818: "Admitted" fails due to undefined universe anomaly after calling
+  "destruct"
+- #4823: remote counter: avoid thread race on sockets
+- #4841: -verbose flag changed semantics in 8.5, is much harder to use
+- #4851: [nsatz] cannot handle duplicated hypotheses
+- #4858: Anomaly: Uncaught exception Failure("hd"). Please report. in variant
+  of nsatz
+- #4880: [nsatz_compute] generates invalid certificates if given redundant
+  hypotheses
+- #4881: synchronizing "Declare Implicit Tactic" with backtrack.
+- #4882: anomaly with Declare Implicit Tactic on hole of type with evars
+- Fix use of "Declare Implicit Tactic" in refine.
+  triggered by CoqIDE
+- #4069, #4718: congruence fails when universes are involved.
+
+Universes
+
+- Disallow silently dropping universe instances applied to variables
+  (forward compatible)
+- Allow explicit universe instances on notations, when they can apply
+  to the head reference of their expansion.
+
+Build infrastructure
+
+- New update on how to find camlp5 binary and library at configure time.
+
+Details of changes in 8.5pl3
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Critical bugfix
+
+- #4876: Guard checker incompleteness when using primitive projections
+
+Other bugfixes
+
+- #4780: Induction with universe polymorphism on was creating ill-typed terms.
+- #4673: regression in setoid_rewrite, unfolding let-ins for type unification.
+- #4754: Regression in setoid_rewrite, allow postponed unification problems to remain.
+- #4769: Anomaly with universe polymorphic schemes defined inside sections.
+- #3886: Program: duplicate obligations of mutual fixpoints.
+- #4994: Documentation typo.
+- #5008: Use the "md5" command on OpenBSD.
+- #5007: Do not assume the "TERM" environment variable is always set.
+- #4606: Output a break before a list only if there was an empty line.
+- #5001: metas not cleaned properly in clenv_refine_in.
+- #2336: incorrect glob data for module symbols (bug #2336).
+- #4832: Remove extraneous dot in error message.
+- Anomaly in printing a unification error message.
+- #4947: Options which take string arguments are not backwards compatible.
+- #4156: micromega cache files are now hidden files.
+- #4871: interrupting par:abstract kills coqtop.
+- #5043: [Admitted] lemmas pick up section variables.
+- Fix name of internal refine ("simple refine").
+- #5062: probably a typo in Strict Proofs mode.
+- #5065: Anomaly: Not a proof by induction.
+- Restore native compiler optimizations, they were disabled since 8.5!
+- #5077: failure on typing a fixpoint with evars in its type.
+- Fix recursive notation bug.
+- #5095: non relevant too strict test in let-in abstraction.
+- Ensuring that the evar name is preserved by "rename".
+- #4887: confusion between using and with in documentation of firstorder.
+- Bug in subst with let-ins.
+- #4762: eauto weaker than auto.
+- Remove if_then_else (was buggy). Use tryif instead.
+- #4970: confusion between special "{" and non special "{{" in notations.
+- #4529: primitive projections unfolding.
+- #4416: Incorrect "Error: Incorrect number of goals".
+- #4863: abstract in typeclass hint fails.
+- #5123: unshelve can impact typeclass resolution
+- Fix a collision about the meta-variable ".." in recursive notations.
+- Fix printing of info_auto.
+- #3209: Not_found due to an occur-check cycle.
+- #5097: status of evars refined by "clear" in ltac: closed wrt evars.
+- #5150: Missing dependency of the test-suite subsystems in prerequisite.
+- Fix a bug in error printing of unif constraints
+- #3941: Do not stop propagation of signals when Coq is busy.
+- #4822: Incorrect assertion in cbn.
+- #3479 parsing of "{" and "}" when a keyword starts with "{" or "}".
+- #5127: Memory corruption with the VM.
+- #5102: bullets parsing broken by calls to parse_entry.
+
+Various documentation improvements
+
 Version 8.4
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 Coq version 8.4 contains the result of three long-term projects: a new
 modular library of arithmetic by Pierre Letouzey, a new proof engine by
 Arnaud Spiwack and a new communication protocol for |CoqIDE| by Vincent
@@ -812,9 +2514,365 @@ Eelis van der Weegen.
 | Hugo Herbelin
 |
 
+Details of changes in 8.4beta
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Logic
+
+- Standard eta-conversion now supported (dependent product only).
+- Guard condition improvement: subterm property is propagated through beta-redex
+  blocked by pattern-matching, as in "(match v with C .. => fun x => u end) x";
+  this allows for instance to use "rewrite ... in ..." without breaking
+  the guard condition.
+
+Specification language and notations
+
+- Maximal implicit arguments can now be set locally by { }. The registration
+  traverses fixpoints and lambdas. Because there is conversion in types,
+  maximal implicit arguments are not taken into account in partial
+  applications (use eta expanded form with explicit { } instead).
+- Added support for recursive notations with binders (allows for instance
+  to write "exists x y z, P").
+- Structure/Record printing can be disable by "Unset Printing Records".
+  In addition, it can be controlled on type by type basis using
+  "Add Printing Record" or "Add Printing Constructor".
+- Pattern-matching compilation algorithm: in "match x, y with ... end",
+  possible dependencies of x (or of the indices of its type) in the type
+  of y are now taken into account.
+
+Tactics
+
+- New proof engine.
+- Scripts can now be structured thanks to bullets - * + and to subgoal
+  delimitation via { }. Note: for use with Proof General, a cvs version of
+  Proof General no older than mid-July 2011 is currently required.
+- Support for tactical "info" is suspended.
+- Support for command "Show Script" is suspended.
+- New tactics constr_eq, is_evar and has_evar for use in Ltac (DOC TODO).
+- Removed the two-argument variant of "decide equality".
+- New experimental tactical "timeout <n> <tac>". Since <n> is a time
+  in second for the moment, this feature should rather be avoided
+  in scripts meant to be machine-independent.
+- Fix in "destruct": removal of unexpected local definitions in context might
+  result in some rare incompatibilities (solvable by adapting name hypotheses).
+- Introduction pattern "_" made more robust.
+- Tactic (and Eval command) vm_compute can now be interrupted via Ctrl-C.
+- Unification in "apply" supports unification of patterns of the form
+  ?f x y = g(x,y) (compatibility ensured by using
+  "Unset Tactic Pattern Unification"). It also supports (full) betaiota.
+- Tactic autorewrite does no longer instantiate pre-existing
+  existential variables (theoretical source of possible incompatibilities).
+- Tactic "dependent rewrite" now supports equality in "sig".
+- Tactic omega now understands Zpred (wish #1912) and can prove any goal
+  from a context containing an arithmetical contradiction (wish #2236).
+- Using "auto with nocore" disables the use of the "core" database (wish #2188).
+  This pseudo-database "nocore" can also be used with trivial and eauto.
+- Tactics "set", "destruct" and "induction" accepts incomplete terms and
+  use the goal to complete the pattern assuming it is non ambiguous.
+- When used on arguments with a dependent type, tactics such as
+  "destruct", "induction", "case", "elim", etc. now try to abstract
+  automatically the dependencies over the arguments of the types
+  (based on initial ideas from Chung-Kil Hur, extension to nested
+  dependencies suggested by Dan Grayson)
+- Tactic "injection" now failing on an equality showing no constructors while
+  it was formerly generalizing again the goal over the given equality.
+- In Ltac, the "context [...]" syntax has now a variant "appcontext [...]"
+  allowing to match partial applications in larger applications.
+- When applying destruct or inversion on a fixpoint hiding an inductive
+  type, recursive calls to the fixpoint now remain folded by default (rare
+  source of incompatibility generally solvable by adding a call to simpl).
+- In an ltac pattern containing a "match", a final "| _ => _" branch could be
+  used now instead of enumerating all remaining constructors. Moreover, the
+  pattern "match _ with _ => _ end" now allows to match any "match". A "in"
+  annotation can also be added to restrict to a precise inductive type.
+- The behavior of "simpl" can be tuned using the "Arguments" vernacular.
+  In particular constants can be marked so that they are always/never unfolded
+  by "simpl", or unfolded only when a set of arguments evaluates to a
+  constructor. Last one can mark a constant so that it is unfolded only if the
+  simplified term does not expose a match in head position.
+
+Vernacular commands
+
+- It is now mandatory to have a space (or tabulation or newline or end-of-file)
+  after a "." ending a sentence.
+- In SearchAbout, the [ ] delimiters are now optional.
+- New command "Add/Remove Search Blacklist <substring> ...":
+  a Search or SearchAbout or similar query will never mention lemmas
+  whose qualified names contain any of the declared substrings.
+  The default blacklisted substrings are ``_subproof``, ``Private_``.
+- When the output file of "Print Universes" ends in ".dot" or ".gv",
+  the universe graph is printed in the DOT language, and can be
+  processed by Graphviz tools.
+- New command "Print Sorted Universes".
+- The undocumented and obsolete option "Set/Unset Boxed Definitions" has
+  been removed, as well as syntaxes like "Boxed Fixpoint foo".
+- A new option "Set Default Timeout n / Unset Default Timeout".
+- Qed now uses information from the reduction tactics used in proof script
+  to avoid conversion at Qed time to go into a very long computation.
+- New command "Show Goal ident" to display the statement of a goal, even
+  a closed one (available from Proof General).
+- Command "Proof" accept a new modifier "using" to force generalization
+  over a given list of section variables at section ending (DOC TODO).
+- New command "Arguments" generalizing "Implicit Arguments" and
+  "Arguments Scope" and that also allows to rename the parameters of a
+  definition and to tune the behavior of the tactic "simpl".
+
+Module System
+
+- During subtyping checks, an opaque constant in a module type could now
+  be implemented by anything of the right type, even if bodies differ.
+  Said otherwise, with respect to subtyping, an opaque constant behaves
+  just as a parameter. Coqchk was already implementing this, but not coqtop.
+- The inlining done during application of functors can now be controlled
+  more precisely, by the annotations (no inline) or (inline at level XX).
+  With the latter annotation, only functor parameters whose levels
+  are lower or equal than XX will be inlined.
+  The level of a parameter can be fixed by "Parameter Inline(30) foo".
+  When levels aren't given, the default value is 100. One can also use
+  the flag "Set Inline Level ..." to set a level (DOC TODO).
+- Print Assumptions should now handle correctly opaque modules (#2168).
+- Print Module (Type) now tries to print more details, such as types and
+  bodies of the module elements. Note that Print Module Type could be
+  used on a module to display only its interface. The option
+  "Set Short Module Printing" could be used to switch back to the earlier
+  behavior were only field names were displayed.
+
+Libraries
+
+- Extension of the abstract part of Numbers, which now provide axiomatizations
+  and results about many more integer functions, such as pow, gcd, lcm, sqrt,
+  log2 and bitwise functions. These functions are implemented for nat, N, BigN,
+  Z, BigZ. See in particular file NPeano for new functions about nat.
+
+- The definition of types positive, N, Z is now in file BinNums.v
+
+- Major reorganization of ZArith. The initial file ZArith/BinInt.v now contains
+  an internal module Z implementing the Numbers interface for integers.
+  This module Z regroups:
+
+  * all functions over type Z : Z.add, Z.mul, ...
+  * the minimal proofs of specifications for these functions : Z.add_0_l, ...
+  * an instantation of all derived properties proved generically in Numbers :
+    Z.add_comm, Z.add_assoc, ...
+
+  A large part of ZArith is now simply compatibility notations, for instance
+  Zplus_comm is an alias for Z.add_comm. The direct use of module Z is now
+  recommended instead of relying on these compatibility notations.
+
+- Similar major reorganization of NArith, via a module N in NArith/BinNat.v
+
+- Concerning the positive datatype, BinPos.v is now in a specific directory
+  PArith, and contains an internal submodule Pos. We regroup there functions
+  such as Pos.add Pos.mul etc as well as many results about them. These results
+  are here proved directly (no Number interface for strictly positive numbers).
+
+- Note that in spite of the compatibility layers, all these reorganizations
+  may induce some marginal incompatibilies in scripts. In particular:
+
+  * the "?=" notation for positive now refers to a binary function Pos.compare,
+    instead of the infamous ternary Pcompare (now Pos.compare_cont).
+  * some hypothesis names generated by the system may changed (typically for
+    a "destruct Z_le_gt_dec") since naming is done after the short name of
+    the head predicate (here now "le" in module Z instead of "Zle", etc).
+  * the internals of Z.add has changed, now relying of Z.pos_sub.
+
+- Also note these new notations:
+
+  * "<?" "<=?" "=?" for boolean tests such as Z.ltb Z.leb Z.eqb.
+  * "÷" for the alternative integer division Z.quot implementing the Truncate
+    convention (former ZOdiv), while the notation for the Coq usual division
+    Z.div implementing the Flooring convention remains "/". Their corresponding
+    modulo functions are Z.rem (no notations) for Z.quot and Z.modulo (infix
+    "mod" notation) for Z.div.
+
+- Lemmas about conversions between these datatypes are also organized
+  in modules, see for instance modules Z2Nat, N2Z, etc.
+
+- When creating BigN, the macro-generated part NMake_gen is much smaller.
+  The generic part NMake has been reworked and improved. Some changes
+  may introduce incompatibilities. In particular, the order of the arguments
+  for BigN.shiftl and BigN.shiftr is now reversed: the number to shift now
+  comes first. By default, the power function now takes two BigN.
+
+- Creation of Vector, an independent library for lists indexed by their length.
+  Vectors' names overwrite lists' one so you should not "Import" the library.
+  All old names changed: function names follow the ocaml ones and, for example,
+  Vcons becomes Vector.cons. You can get [..;..;..]-style notations by importing
+  Vector.VectorNotations.
+
+- Removal of TheoryList. Requiring List instead should work most of the time.
+
+- New syntax "rew Heq in H" and "rew <- Heq in H" for eq_rect and
+  eq_rect_r (available by importing module EqNotations).
+
+- Wf.iter_nat is now Peano.nat_iter (with an implicit type argument).
+
+Internal infrastructure
+
+- Opaque proofs are now loaded lazily by default. This allows to be almost as
+  fast as -dont-load-proofs, while being safer (no creation of axioms) and
+  avoiding feature restrictions (Print and Print Assumptions work ok).
+- Revised hash-consing code allowing more sharing of memory
+- Experimental support added for camlp4 (the one provided alongside ocaml),
+  simply pass option -usecamlp4 to ./configure. By default camlp5 is used.
+- Revised build system: no more stages in Makefile thanks to some recursive
+  aspect of recent gnu make, use of vo.itarget files containing .v to compile
+  for both make and ocamlbuild, etc.
+- Support of cross-compilation via mingw from unix toward Windows,
+  contact P. Letouzey for more informations.
+- New Makefile rules mli-doc to make html of mli in dev/doc/html and
+  full-stdlib to get a (huge) pdf reflecting the whole standard library.
+
+Extraction
+
+- By default, opaque terms are now truly considered opaque by extraction:
+  instead of accessing their body, they are now considered as axioms.
+  The previous behaviour can be reactivated via the option
+  "Set Extraction AccessOpaque".
+- The pretty-printer for Haskell now produces layout-independent code
+- A new command "Separate Extraction cst1 cst2 ..." that mixes a
+  minimal extracted environment a la "Recursive Extraction" and the
+  production of several files (one per coq source) a la "Extraction Library"
+  (DOC TODO).
+- New option "Set/Unset Extraction KeepSingleton" for preventing the
+  extraction to optimize singleton container types (DOC TODO).
+- The extraction now identifies and properly rejects a particular case of
+  universe polymorphism it cannot handle yet (the pair (I,I) being Prop).
+- Support of anonymous fields in record (#2555).
+
+CoqIDE
+
+- Coqide now runs coqtop as separated process, making it more robust:
+  coqtop subprocess can be interrupted, or even killed and relaunched
+  (cf button "Restart Coq", ex-"Go to Start"). For allowing such
+  interrupts, the Windows version of coqide now requires Windows >= XP
+  SP1.
+- The communication between CoqIDE and Coqtop is now done via a dialect
+  of XML (DOC TODO).
+- The backtrack engine of CoqIDE has been reworked, it now uses the
+  "Backtrack" command similarly to Proof General.
+- The Coqide parsing of sentences has be reworked and now supports
+  tactic delimitation via { }.
+- Coqide now accepts the Abort command (wish #2357).
+- Coqide can read coq_makefile files as "project file" and use it to
+  set automatically options to send to coqtop.
+- Preference files have moved to $XDG_CONFIG_HOME/coq and accelerators
+  are not stored as a list anymore.
+
+Tools
+
+- Coq now searches directories specified in COQPATH, $XDG_DATA_HOME/coq,
+  $XDG_DATA_DIRS/coq, and user-contribs before the standard library.
+
+- Coq rc file has moved to $XDG_CONFIG_HOME/coq.
+
+- Major changes to coq_makefile:
+
+  * mli/mlpack/mllib taken into account, ml not preproccessed anymore, ml4 work;
+  * mlihtml generates doc of mli, install-doc install the html doc in DOCDIR
+    with the same policy as vo in COQLIB;
+  * More variables are given by coqtop -config, others are defined only if the
+    users doesn't have defined them elsewhere. Consequently, generated makefile
+    should work directly on any architecture;
+  * Packagers can take advantage of $(DSTROOT) introduction. Installation can
+    be made in $XDG_DATA_HOME/coq;
+  * -arg option allows to send option as argument to coqc.
+
+Details of changes in 8.4beta2
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Vernacular commands
+
+- Commands "Back" and "BackTo" are now handling the proof states. They may
+  perform some extra steps of backtrack to avoid states where the proof
+  state is unavailable (typically a closed proof).
+- The commands "Suspend" and "Resume" have been removed.
+- A basic Show Script has been reintroduced (no indentation).
+- New command "Set Parsing Explicit" for deactivating parsing (and printing)
+  of implicit arguments (useful for teaching).
+- New command "Grab Existential Variables" to transform the unresolved evars
+  at the end of a proof into goals.
+
+Tactics
+
+- Still no general "info" tactical, but new specific tactics info_auto,
+  info_eauto, info_trivial which provides information on the proofs found
+  by auto/eauto/trivial. Display of these details could also be activated by
+  "Set Info Auto"/"Set Info Eauto"/"Set Info Trivial".
+- Details on everything tried by auto/eauto/trivial during a proof search
+  could be obtained by "debug auto", "debug eauto", "debug trivial" or by a
+  global "Set Debug Auto"/"Set Debug Eauto"/"Set Debug Trivial".
+- New command "r string" in Ltac debugger that interprets "idtac
+  string" in Ltac code as a breakpoint and jumps to its next use.
+- Tactics from the Dp plugin (simplify, ergo, yices, cvc3, z3, cvcl,
+  harvey, zenon, gwhy) have been removed, since Why2 has not been
+  maintained for the last few years. The Why3 plugin should be a suitable
+  replacement in most cases.
+
+Libraries
+
+- MSetRBT: a new implementation of MSets via Red-Black trees (initial
+  contribution by Andrew Appel).
+- MSetAVL: for maximal sharing with the new MSetRBT, the argument order
+  of Node has changed (this should be transparent to regular MSets users).
+
+Module System
+
+- The names of modules (and module types) are now in a fully separated
+  namespace from ordinary definitions: "Definition E:=0. Module E. End E."
+  is now accepted.
+
+CoqIDE
+
+- Coqide now supports the "Restart" command, and "Undo" (with a warning).
+  Better support for "Abort".
+
+Details of changes in 8.4
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Vernacular commands
+
+- The "Reset" command is now supported again in files given to coqc or Load.
+- "Show Script" now indents again the displayed scripts. It can also work
+  correctly across Load'ed files if the option "Unset Atomic Load" is used.
+- "Open Scope" can now be given the delimiter (e.g. Z) instead of the full
+  scope name (e.g. Z_scope).
+
+Notations
+
+- Most compatibility notations of the standard library are now tagged as
+  (compat xyz), where xyz is a former Coq version, for instance "8.3".
+  These notations behave as (only parsing) notations, except that they may
+  triggers warnings (or errors) when used while Coq is not in a corresponding
+  -compat mode.
+- To activate these compatibility warnings, use "Set Verbose Compat Notations"
+  or the command-line flag -verbose-compat-notations.
+- For a strict mode without these compatibility notations, use
+  "Unset Compat Notations" or the command-line flag -no-compat-notations.
+
+Tactics
+
+- An annotation "eqn:H" or "eqn:?" can be added to a "destruct"
+  or "induction" to make it generate equations in the spirit of "case_eq".
+  The former syntax "_eqn" is discontinued.
+- The name of the hypothesis introduced by tactic "remember" can be
+  set via the new syntax "remember t as x eqn:H" (wish #2489).
+
+Libraries
+
+- Reals: changed definition of PI, no more axiom about sin(PI/2).
+- SetoidPermutation: a notion of permutation for lists modulo a setoid equality.
+- BigN: fixed the ocaml code doing the parsing/printing of big numbers.
+- List: a couple of lemmas added especially about no-duplication, partitions.
+- Init: Removal of the coercions between variants of sigma-types and
+  subset types (possible source of incompatibility).
+
 Version 8.3
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 Coq version 8.3 is before all a transition version with refinements or
 extensions of the existing features and libraries and a new tactic nsatz
 based on Hilbert’s Nullstellensatz for deciding systems of equations
@@ -886,9 +2944,356 @@ Pierce for the excellent teaching materials they provided.
 | Hugo Herbelin
 |
 
+Details of changes
+~~~~~~~~~~~~~~~~~~
+
+Rewriting tactics
+
+- Tactic "rewrite" now supports rewriting on ad hoc equalities such as eq_true.
+- "Hint Rewrite" now checks that the lemma looks like an equation.
+- New tactic "etransitivity".
+- Support for heterogeneous equality (JMeq) in "injection" and "discriminate".
+- Tactic "subst" now supports heterogeneous equality and equality
+  proofs that are dependent (use "simple subst" for preserving compatibility).
+- Added support for Leibniz-rewriting of dependent hypotheses.
+- Renamed "Morphism" into "Proper" and "respect" into "proper_prf"
+  (possible source of incompatibility). A partial fix is to define
+  "Notation Morphism R f := (Proper (R%signature) f)."
+- New tactic variants "rewrite* by" and "autorewrite*" that rewrite
+  respectively the first and all matches whose side-conditions are
+  solved.
+- "Require Import Setoid" does not export all of "Morphisms" and
+  "RelationClasses" anymore (possible source of incompatibility, fixed
+  by importing "Morphisms" too).
+- Support added for using Chung-Kil Hur's Heq library for rewriting over
+  heterogeneous equality (courtesy of the library's author).
+- Tactic "replace" supports matching terms with holes.
+
+Automation tactics
+
+- Tactic ``intuition`` now preserves inner ``iff`` and ``not`` (exceptional
+  source of incompatibilities solvable by redefining ``intuition`` as
+  ``unfold iff, not in *; intuition``, or, for iff only, by using
+  ``Set Intuition Iff Unfolding``.)
+- Tactic ``tauto`` now proves classical tautologies as soon as classical logic
+  (i.e. library ``Classical_Prop`` or ``Classical``) is loaded.
+- Tactic ``gappa`` has been removed from the Dp plugin.
+- Tactic ``firstorder`` now supports the combination of its ``using`` and
+  ``with`` options.
+- New ``Hint Resolve ->`` (or ``<-``) for declaring iff's as oriented
+  hints (wish #2104).
+- An inductive type as argument of the ``using`` option of ``auto`` / ``eauto`` / ``firstorder``
+  is interpreted as using the collection of its constructors.
+- New decision tactic "nsatz" to prove polynomial equations
+  by computation of Groebner bases.
+
+Other tactics
+
+- Tactic "discriminate" now performs intros before trying to discriminate an
+  hypothesis of the goal (previously it applied intro only if the goal
+  had the form t1<>t2) (exceptional source of incompatibilities - former
+  behavior can be obtained by "Unset Discriminate Introduction").
+- Tactic "quote" now supports quotation of arbitrary terms (not just the
+  goal).
+- Tactic "idtac" now displays its "list" arguments.
+- New introduction patterns "*" for introducing the next block of dependent
+  variables and "**" for introducing all quantified variables and hypotheses.
+- Pattern Unification for existential variables activated in tactics and
+  new option "Unset Tactic Evars Pattern Unification" to deactivate it.
+- Resolution of canonical structure is now part of the tactic's unification
+  algorithm.
+- New tactic "decide lemma with hyp" for rewriting decidability lemmas
+  when one knows which side is true.
+- Improved support of dependent goals over objects in dependent types for
+  "destruct" (rare source of incompatibility that can be avoided by unsetting
+  option "Dependent Propositions Elimination").
+- Tactic "exists", "eexists", "destruct" and "edestruct" supports iteration
+  using comma-separated arguments.
+- Tactic names "case" and "elim" now support clauses "as" and "in" and become
+  then synonymous of "destruct" and "induction" respectively.
+- A new tactic name "exfalso" for the use of 'ex-falso quodlibet' principle.
+  This tactic is simply a shortcut for "elimtype False".
+- Made quantified hypotheses get the name they would have if introduced in
+  the context (possible but rare source of incompatibilities).
+- When applying a component of a conjunctive lemma, "apply in" (and
+  sequences of "apply in") now leave the side conditions of the lemmas
+  uniformly after the main goal (possible source of rare incompatibilities).
+- In "simpl c" and "change c with d", c can be a pattern.
+- Tactic "revert" now preserves let-in's making it the exact inverse of
+  "intro".
+- New tactics "clear dependent H" and "revert dependent H" that
+  clears (resp. reverts) H and all the hypotheses that depend on H.
+- Ltac's pattern-matching now supports matching metavariables that
+  depend on variables bound upwards in the pattern.
+
+Tactic definitions
+
+- Ltac definitions support Local option for non-export outside modules.
+- Support for parsing non-empty lists with separators in tactic notations.
+- New command "Locate Ltac" to get the full name of an Ltac definition.
+
+Notations
+
+- Record syntax ``{|x=...; y=...|}`` now works inside patterns too.
+- Abbreviations from non-imported module now invisible at printing time.
+- Abbreviations now use implicit arguments and arguments scopes for printing.
+- Abbreviations to pure names now strictly behave like the name they refer to
+  (make redirections of qualified names easier).
+- Abbreviations for applied constant now propagate the implicit arguments
+  and arguments scope of the underlying reference (possible source of
+  incompatibilities generally solvable by changing such abbreviations from
+  e.g. ``Notation foo' := (foo x)`` to ``Notation foo' y := (foo x (y:=y))``).
+- The "where" clause now supports multiple notations per defined object.
+- Recursive notations automatically expand one step on the left for better
+  factorization; recursion notations inner separators now ensured being tokens.
+- Added "Reserved Infix" as a specific shortcut of the corresponding
+  "Reserved Notation".
+- Open/Close Scope command supports Global option in sections.
+
+Specification language
+
+- New support for local binders in the syntax of Record/Structure fields.
+- Fixpoint/CoFixpoint now support building part or all of bodies using tactics.
+- Binders given before ":" in lemmas and in definitions built by tactics are
+  now automatically introduced (possible source of incompatibility that can
+  be resolved by invoking "Unset Automatic Introduction").
+- New support for multiple implicit arguments signatures per reference.
+
+Module system
+
+- Include Type is now deprecated since Include now accept both modules and
+  module types.
+- Declare ML Module supports Local option.
+- The sharing between non-logical object and the management of the
+  name-space has been improved by the new "Delta-equivalence" on
+  qualified name.
+- The include operator has been extended to high-order structures
+- Sequences of Include can be abbreviated via new syntax "<+".
+- A module (or module type) can be given several "<:" signatures.
+- Interactive proofs are now permitted in module type. Functors can hence
+  be declared as Module Type and be used later to type themselves.
+- A functor application can be prefixed by a "!" to make it ignore any
+  "Inline" annotation in the type of its argument(s) (for examples of
+  use of the new features, see libraries Structures and Numbers).
+- Coercions are now active only when modules are imported (use "Set Automatic
+  Coercions Import" to get the behavior of the previous versions of Coq).
+
+Extraction
+
+- When using (Recursive) Extraction Library, the filenames are directly the
+  Coq ones with new appropriate extensions : we do not force anymore
+  uncapital first letters for Ocaml and capital ones for Haskell.
+- The extraction now tries harder to avoid code transformations that can be
+  dangerous for the complexity. In particular many eta-expansions at the top
+  of functions body are now avoided, clever partial applications will likely
+  be preserved, let-ins are almost always kept, etc.
+- In the same spirit, auto-inlining is now disabled by default, except for
+  induction principles, since this feature was producing more frequently
+  weird code than clear gain. The previous behavior can be restored via
+  "Set Extraction AutoInline".
+- Unicode characters in identifiers are now transformed into ascii strings
+  that are legal in Ocaml and other languages.
+- Harsh support of module extraction to Haskell and Scheme: module hierarchy
+  is flattened, module abbreviations and functor applications are expanded,
+  module types and unapplied functors are discarded.
+- Less unsupported situations when extracting modules to Ocaml. In particular
+  module parameters might be alpha-renamed if a name clash is detected.
+- Extract Inductive is now possible toward non-inductive types (e.g. nat => int)
+- Extraction Implicit: this new experimental command allows to mark
+  some arguments of a function or constructor for removed during
+  extraction, even if these arguments don't fit the usual elimination
+  principles of extraction, for instance the length n of a vector.
+- Files ExtrOcaml*.v in plugins/extraction try to provide a library of common
+  extraction commands: mapping of basics types toward Ocaml's counterparts,
+  conversions from/to int and big_int, or even complete mapping of nat,Z,N
+  to int or big_int, or mapping of ascii to char and string to char list
+  (in this case recognition of ascii constants is hard-wired in the extraction).
+
+Program
+
+- Streamlined definitions using well-founded recursion and measures so
+  that they can work on any subset of the arguments directly (uses currying).
+- Try to automatically clear structural fixpoint prototypes in
+  obligations to avoid issues with opacity.
+- Use return type clause inference in pattern-matching as in the standard
+  typing algorithm.
+- Support [Local Obligation Tactic] and [Next Obligation with tactic].
+- Use [Show Obligation Tactic] to print the current default tactic.
+- [fst] and [snd] have maximal implicit arguments in Program now (possible
+  source of incompatibility).
+
+Type classes
+
+- Declaring axiomatic type class instances in Module Type should be now
+  done via new command "Declare Instance", while the syntax "Instance"
+  now always provides a concrete instance, both in and out of Module Type.
+- Use [Existing Class foo] to declare foo as a class a posteriori.
+  [foo] can be an inductive type or a constant definition. No
+  projections or instances are defined.
+- Various bug fixes and improvements: support for defined fields,
+  anonymous instances, declarations giving terms, better handling of
+  sections and [Context].
+
+Vernacular commands
+
+- New command "Timeout <n> <command>." interprets a command and a timeout
+  interrupts the interpretation after <n> seconds.
+- New command "Compute <expr>." is a shortcut for "Eval vm_compute in <expr>".
+- New command "Fail <command>." interprets a command and is successful iff
+  the command fails on an error (but not an anomaly). Handy for tests and
+  illustration of wrong commands.
+- Most commands referring to constant (e.g. Print or About) now support
+  referring to the constant by a notation string.
+- New option "Boolean Equality Schemes" to make generation of boolean
+  equality automatic for datatypes (together with option "Decidable
+  Equality Schemes", this replaces deprecated option "Equality Scheme").
+- Made support for automatic generation of case analysis schemes available
+  to user (governed by option "Set Case Analysis Schemes").
+- New command :n:`{? Global } Generalizable [All|No] [Variable|Variables] {* @ident}` to
+  declare which identifiers are generalizable in `` `{} `` and `` `() `` binders.
+- New command "Print Opaque Dependencies" to display opaque constants in
+  addition to all variables, parameters or axioms a theorem or
+  definition relies on.
+- New command "Declare Reduction <id> := <conv_expr>", allowing to write
+  later "Eval <id> in ...". This command accepts a Local variant.
+- Syntax of Implicit Type now supports more than one block of variables of
+  a given type.
+- Command "Canonical Structure" now warns when it has no effects.
+- Commands of the form "Set X" or "Unset X" now support "Local" and "Global"
+  prefixes.
+
+Library
+
+- Use "standard" Coq names for the properties of eq and identity
+  (e.g. refl_equal is now eq_refl). Support for compatibility is provided.
+
+- The function Compare_dec.nat_compare is now defined directly,
+  instead of relying on lt_eq_lt_dec. The earlier version is still
+  available under the name nat_compare_alt.
+
+- Lemmas in library Relations and Reals have been homogenized a bit.
+
+- The implicit argument of Logic.eq is now maximally inserted, allowing
+  to simply write "eq" instead of "@eq _" in morphism signatures.
+
+- Wrongly named lemmas (Zlt_gt_succ and Zlt_succ_gt) fixed (potential source
+  of incompatibilities)
+
+- List library:
+
+  + Definitions of list, length and app are now in Init/Datatypes.
+    Support for compatibility is provided.
+  + Definition of Permutation is now in Sorting/Permtation.v
+  + Some other light revisions and extensions (possible source
+    of incompatibilities solvable by qualifying names accordingly).
+
+- In ListSet, set_map has been fixed (source of incompatibilities if used).
+
+- Sorting library:
+
+  + new mergesort of worst-case complexity O(n*ln(n)) made available in
+    Mergesort.v;
+  + former notion of permutation up to setoid from Permutation.v is
+    deprecated and moved to PermutSetoid.v;
+  + heapsort from Heap.v of worst-case complexity O(n*n) is deprecated;
+  + new file Sorted.v for some definitions of being sorted.
+
+- Structure library. This new library is meant to contain generic
+  structures such as types with equalities or orders, either
+  in Module version (for now) or Type Classes (still to do):
+
+  + DecidableType.v and OrderedType.v: initial notions for FSets/FMaps,
+    left for compatibility but considered as deprecated.
+  + Equalities.v and Orders.v: evolutions of the previous files,
+    with fine-grain Module architecture, many variants, use of
+    Equivalence and other relevant Type Classes notions.
+  + OrdersTac.v: a generic tactic for solving chains of (in)equalities
+    over variables. See {Nat,N,Z,P}OrderedType.v for concrete instances.
+  + GenericMinMax.v: any ordered type can be equipped with min and max.
+    We derived here all the generic properties of these functions.
+
+- MSets library: an important evolution of the FSets library.
+  "MSets" stands for Modular (Finite) Sets, by contrast with a forthcoming
+  library of Class (Finite) Sets contributed by S. Lescuyer which will be
+  integrated with the next release of Coq. The main features of MSets are:
+
+  + The use of Equivalence, Proper and other Type Classes features
+    easing the handling of setoid equalities.
+  + The interfaces are now stated in iff-style. Old specifications
+    are now derived properties.
+  + The compare functions are now pure, and return a "comparison" value.
+    Thanks to the CompSpec inductive type, reasoning on them remains easy.
+  + Sets structures requiring invariants (i.e. sorted lists) are
+    built first as "Raw" sets (pure objects and separate proofs) and
+    attached with their proofs thanks to a generic functor. "Raw" sets
+    have now a proper interface and can be manipulated directly.
+
+  Note: No Maps yet in MSets. The FSets library is still provided
+  for compatibility, but will probably be considered as deprecated in the
+  next release of Coq.
+
+- Numbers library:
+
+  + The abstract layer (NatInt, Natural/Abstract, Integer/Abstract) has
+    been simplified and enhance thanks to new features of the module
+    system such as Include (see above). It has been extended to Euclidean
+    division (three flavors for integers: Trunc, Floor and Math).
+  + The arbitrary-large efficient numbers (BigN, BigZ, BigQ) has also
+    been reworked. They benefit from the abstract layer improvements
+    (especially for div and mod). Note that some specifications have
+    slightly changed (compare, div, mod, shift{r,l}). Ring/Field should
+    work better (true recognition of constants).
+
+Tools
+
+- Option -R now supports binding Coq root read-only.
+- New coqtop/coqc option -beautify to reformat .v files (usable
+  e.g. to globally update notations).
+- New tool beautify-archive to beautify a full archive of developments.
+- New coqtop/coqc option -compat X.Y to simulate the general behavior
+  of previous versions of Coq (provides e.g. support for 8.2 compatibility).
+
+Coqdoc
+
+- List have been revamped.  List depth and scope is now determined by
+  an "offside" whitespace rule.
+- Text may be italicized by placing it in _underscores_.
+- The "--index <string>" flag changes the filename of the index.
+- The "--toc-depth <int>" flag limits the depth of headers which are
+  included in the table of contents.
+- The "--lib-name <string>" flag prints "<string> Foo" instead of
+  "Library Foo" where library titles are called for.  The
+  "--no-lib-name" flag eliminates the extra title.
+- New option "--parse-comments" to allow parsing of regular ``(* *)``
+  comments.
+- New option "--plain-comments" to disable interpretation inside comments.
+- New option "--interpolate" to try and typeset identifiers in Coq escapings
+  using the available globalization information.
+- New option "--external url root" to refer to external libraries.
+- Links to section variables and notations now supported.
+
+Internal infrastructure
+
+- To avoid confusion with the repository of user's contributions,
+  the subdirectory "contrib" has been renamed into "plugins".
+  On platforms supporting ocaml native dynlink, code located there
+  is built as loadable plugins for coqtop.
+- An experimental build mechanism via ocamlbuild is provided.
+  From the top of the archive, run ./configure as usual, and
+  then ./build. Feedback about this build mechanism is most welcome.
+  Compiling Coq on platforms such as Windows might be simpler
+  this way, but this remains to be tested.
+- The Makefile system has been simplified and factorized with
+  the ocamlbuild system. In particular "make" takes advantage
+  of .mllib files for building .cma/.cmxa. The .vo files to
+  compile are now listed in several vo.itarget files.
+
 Version 8.2
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 Coq version 8.2 adds new features, new libraries and improves on many
 various aspects.
 
@@ -980,9 +3385,543 @@ the Coq-Club mailing list.
 | Hugo Herbelin
 |
 
+Details of changes
+~~~~~~~~~~~~~~~~~~
+
+Language
+
+- If a fixpoint is not written with an explicit { struct ... }, then
+  all arguments are tried successively (from left to right) until one is
+  found that satisfies the structural decreasing condition.
+- New experimental typeclass system giving ad-hoc polymorphism and
+  overloading based on dependent records and implicit arguments.
+- New syntax "let 'pat := b in c" for let-binding using irrefutable patterns.
+- New syntax "forall {A}, T" for specifying maximally inserted implicit
+  arguments in terms.
+- Sort of Record/Structure, Inductive and CoInductive defaults to Type
+  if omitted.
+- (Co)Inductive types can be defined as records
+  (e.g. "CoInductive stream := { hd : nat; tl : stream }.")
+- New syntax "Theorem id1:t1 ... with idn:tn" for proving mutually dependent
+  statements.
+- Support for sort-polymorphism on constants denoting inductive types.
+- Several evolutions of the module system (handling of module aliases,
+  functorial module types, an Include feature, etc).
+- Prop now a subtype of Set (predicative and impredicative forms).
+- Recursive inductive types in Prop with a single constructor of which
+  all arguments are in Prop is now considered to be a singleton
+  type. It consequently supports all eliminations to Prop, Set and Type.
+  As a consequence, Acc_rect has now a more direct proof [possible source
+  of easily fixed incompatibility in case of manual definition of a recursor
+  in a recursive singleton inductive type].
+
+Vernacular commands
+
+- Added option Global to "Arguments Scope" for section surviving.
+- Added option "Unset Elimination Schemes" to deactivate the automatic
+  generation of elimination schemes.
+- Modification of the Scheme command so you can ask for the name to be
+  automatically computed (e.g. Scheme Induction for nat Sort Set).
+- New command "Combined Scheme" to build combined mutual induction
+  principles from existing mutual induction principles.
+- New command "Scheme Equality" to build a decidable (boolean) equality
+  for simple inductive datatypes and a decision property over this equality
+  (e.g.  Scheme Equality for nat).
+- Added option "Set Equality Scheme" to make automatic the declaration
+  of the boolean equality when possible.
+- Source of universe inconsistencies now printed when option
+  "Set Printing Universes" is activated.
+- New option "Set Printing Existential Instances" for making the display of
+  existential variable instances explicit.
+- Support for option "[id1 ... idn]", and "-[id1 ... idn]", for the
+  "compute"/"cbv" reduction strategy, respectively meaning reduce only, or
+  everything but, the constants id1 ... idn. "lazy" alone or followed by
+  "[id1 ... idn]", and "-[id1 ... idn]" also supported, meaning apply
+  all of beta-iota-zeta-delta, possibly restricting delta.
+- New command "Strategy" to control the expansion of constants during
+  conversion tests. It generalizes commands Opaque and Transparent by
+  introducing a range of levels. Lower levels are assigned to constants
+  that should be expanded first.
+- New options Global and Local to Opaque and Transparent.
+- New command "Print Assumptions" to display all variables, parameters
+  or axioms a theorem or definition relies on.
+- "Add Rec LoadPath" now provides references to libraries using partially
+  qualified names (this holds also for coqtop/coqc option -R).
+- SearchAbout supports negated search criteria, reference to logical objects
+  by their notation, and more generally search of subterms.
+- "Declare ML Module" now allows to import .cmxs files when Coq is
+  compiled in native code with a version of OCaml that supports native
+  Dynlink (>= 3.11).
+- Specific sort constraints on Record now taken into account.
+- "Print LoadPath" supports a path argument to filter the display.
+
+Libraries
+
+- Several parts of the libraries are now in Type, in particular FSets,
+  SetoidList, ListSet, Sorting, Zmisc. This may induce a few
+  incompatibilities. In case of trouble while fixing existing development,
+  it may help to simply declare Set as an alias for Type (see file
+  SetIsType).
+
+- New arithmetical library in theories/Numbers. It contains:
+
+  * an abstract modular development of natural and integer arithmetics
+    in Numbers/Natural/Abstract and Numbers/Integer/Abstract
+  * an implementation of efficient computational bounded and unbounded
+    integers that can be mapped to processor native arithmetics.
+    See Numbers/Cyclic/Int31 for 31-bit integers and Numbers/Natural/BigN
+    for unbounded natural numbers and Numbers/Integer/BigZ for unbounded
+    integers.
+  * some proofs that both older libraries Arith, ZArith and NArith and
+    newer BigN and BigZ implement the abstract modular development.
+    This allows in particular BigN and BigZ to already come with a
+    large database of basic lemmas and some generic tactics (ring),
+
+  This library has still an experimental status, as well as the
+  processor-acceleration mechanism, but both its abstract and its
+  concrete parts are already quite usable and could challenge the use
+  of nat, N and Z in actual developments. Moreover, an extension of
+  this framework to rational numbers is ongoing, and an efficient
+  Q structure is already provided (see Numbers/Rational/BigQ), but
+  this part is currently incomplete (no abstract layer and generic
+  lemmas).
+
+- Many changes in FSets/FMaps. In practice, compatibility with earlier
+  version should be fairly good, but some adaptations may be required.
+
+  * Interfaces of unordered ("weak") and ordered sets have been factorized
+    thanks to new features of Coq modules (in particular Include), see
+    FSetInterface. Same for maps. Hints in these interfaces have been
+    reworked (they are now placed in a "set" database).
+  * To allow full subtyping between weak and ordered sets, a field
+    "eq_dec" has been added to OrderedType. The old version of OrderedType
+    is now called MiniOrderedType and functor MOT_to_OT allow to
+    convert to the new version. The interfaces and implementations
+    of sets now contain also such a "eq_dec" field.
+  * FSetDecide, contributed by Aaron Bohannon, contains a decision
+    procedure allowing to solve basic set-related goals (for instance,
+    is a point in a particular set ?). See FSetProperties for examples.
+  * Functors of properties have been improved, especially the ones about
+    maps, that now propose some induction principles. Some properties
+    of fold need less hypothesis.
+  * More uniformity in implementations of sets and maps: they all use
+    implicit arguments, and no longer export unnecessary scopes (see
+    bug #1347)
+  * Internal parts of the implementations based on AVL have evolved a
+    lot. The main files FSetAVL and FMapAVL are now much more
+    lightweight now. In particular, minor changes in some functions
+    has allowed to fully separate the proofs of operational
+    correctness from the proofs of well-balancing: well-balancing is
+    critical for efficiency, but not anymore for proving that these
+    trees implement our interfaces, hence we have moved these proofs
+    into appendix files FSetFullAVL and FMapFullAVL. Moreover, a few
+    functions like union and compare have been modified in order to be
+    structural yet efficient. The appendix files also contains
+    alternative versions of these few functions, much closer to the
+    initial Ocaml code and written via the Function framework.
+
+- Library IntMap, subsumed by FSets/FMaps, has been removed from
+  Coq Standard Library and moved into a user contribution Cachan/IntMap
+
+- Better computational behavior of some constants (eq_nat_dec and
+  le_lt_dec more efficient, Z_lt_le_dec and Positive_as_OT.compare
+  transparent, ...) (exceptional source of incompatibilities).
+
+- Boolean operators moved from module Bool to module Datatypes (may need
+  to rename qualified references in script and force notations || and &&
+  to be at levels 50 and 40 respectively).
+
+- The constructors xI and xO of type positive now have postfix notations
+  "~1" and "~0", allowing to write numbers in binary form easily, for instance
+  6 is 1~1~0 and 4*p is p~0~0 (see BinPos.v).
+
+- Improvements to NArith (Nminus, Nmin, Nmax), and to QArith (in particular
+  a better power function).
+
+- Changes in ZArith: several additional lemmas (used in theories/Numbers),
+  especially in Zdiv, Znumtheory, Zpower. Moreover, many results in
+  Zdiv have been generalized: the divisor may simply be non-null
+  instead of strictly positive (see lemmas with name ending by
+  "_full"). An alternative file ZOdiv proposes a different behavior
+  (the one of Ocaml) when dividing by negative numbers.
+
+- Changes in Arith: EqNat and Wf_nat now exported from Arith, some
+  constructions on nat that were outside Arith are now in (e.g. iter_nat).
+
+- In SetoidList, eqlistA now expresses that two lists have similar elements
+  at the same position, while the predicate previously called eqlistA
+  is now equivlistA (this one only states that the lists contain the same
+  elements, nothing more).
+
+- Changes in Reals:
+
+  * Most statement in "sigT" (including the
+    completeness axiom) are now in "sig" (in case of incompatibility,
+    use proj1_sig instead of projT1, sig instead of sigT, etc).
+  * More uniform naming scheme (identifiers in French moved to English,
+    consistent use of 0 -- zero -- instead of O -- letter O --, etc).
+  * Lemma on prod_f_SO is now on prod_f_R0.
+  * Useless hypothesis of ln_exists1 dropped.
+  * New Rlogic.v states a few logical properties about R axioms.
+  * RIneq.v extended and made cleaner.
+
+- Slight restructuration of the Logic library regarding choice and classical
+  logic. Addition of files providing intuitionistic axiomatizations of
+  descriptions: Epsilon.v, Description.v and IndefiniteDescription.v.
+
+- Definition of pred and minus made compatible with the structural
+  decreasing criterion for use in fixpoints.
+
+- Files Relations/Rstar.v and Relations/Newman.v moved out to the user
+  contribution repository (contribution CoC_History). New lemmas about
+  transitive closure added and some bound variables renamed (exceptional
+  risk of incompatibilities).
+
+- Syntax for binders in terms (e.g. for "exists") supports anonymous names.
+
+Notations, coercions, implicit arguments and type inference
+
+- More automation in the inference of the return clause of dependent
+  pattern-matching problems.
+- Experimental allowance for omission of the clauses easily detectable as
+  impossible in pattern-matching problems.
+- Improved inference of implicit arguments.
+- New options "Set Maximal Implicit Insertion", "Set Reversible Pattern
+  Implicit", "Set Strongly Strict Implicit" and "Set Printing Implicit
+  Defensive" for controlling inference and use of implicit arguments.
+- New modifier in "Implicit Arguments" to force an implicit argument to
+  be maximally inserted.
+- New modifier of "Implicit Arguments" to enrich the set of implicit arguments.
+- New options Global and Local to "Implicit Arguments" for section
+  surviving or non export outside module.
+- Level "constr" moved from 9 to 8.
+- Structure/Record now printed as Record (unless option Printing All is set).
+- Support for parametric notations defining constants.
+- Insertion of coercions below product types refrains to unfold
+  constants (possible source of incompatibility).
+- New support for fix/cofix in notations.
+
+Tactic Language
+
+- Second-order pattern-matching now working in Ltac "match" clauses
+  (syntax for second-order unification variable is "@?X").
+- Support for matching on let bindings in match context using syntax
+  "H := body" or "H := body : type".
+- Ltac accepts integer arguments (syntax is "ltac:nnn" for nnn an integer).
+- The general sequence tactical "expr_0 ; [ expr_1 | ... | expr_n ]"
+  is extended so that at most one expr_i may have the form "expr .."
+  or just "..". Also, n can be different from the number of subgoals
+  generated by expr_0. In this case, the value of expr (or idtac in
+  case of just "..") is applied to the intermediate subgoals to make
+  the number of tactics equal to the number of subgoals.
+- A name used as the name of the parameter of a lemma (like f in
+  "apply f_equal with (f:=t)") is now interpreted as a ltac variable
+  if such a variable exists (this is a possible source of
+  incompatibility and it can be fixed by renaming the variables of a
+  ltac function into names that do not clash with the lemmas
+  parameter names used in the tactic).
+- New syntax "Ltac tac ::= ..." to rebind a tactic to a new expression.
+- "let rec ... in ... " now supported for expressions without explicit
+  parameters; interpretation is lazy to the contrary of "let ... in ...";
+  hence, the "rec" keyword can be used to turn the argument of a
+  "let ... in ..." into a lazy one.
+- Patterns for hypotheses types in "match goal" are now interpreted in
+  type_scope.
+- A bound variable whose name is not used elsewhere now serves as
+  metavariable in "match" and it gets instantiated by an identifier
+  (allow e.g. to extract the name of a statement like "exists x, P x").
+- New printing of Ltac call trace for better debugging.
+
+Tactics
+
+- New tactics "apply -> term", "apply <- term", "apply -> term in
+  ident", "apply <- term in ident" for applying equivalences (iff).
+
+- Slight improvement of the hnf and simpl tactics when applied on
+  expressions with explicit occurrences of match or fix.
+
+- New tactics "eapply in", "erewrite", "erewrite in".
+
+- New tactics "ediscriminate", "einjection", "esimplify_eq".
+
+- Tactics "discriminate", "injection", "simplify_eq" now support any
+  term as argument. Clause "with" is also supported.
+
+- Unfoldable references can be given by notation's string rather than by name
+  in unfold.
+
+- The "with" arguments are now typed using informations from the current goal:
+  allows support for coercions and more inference of implicit arguments.
+
+- Application of "f_equal"-style lemmas works better.
+
+- Tactics elim, case, destruct and induction now support variants eelim,
+  ecase, edestruct and einduction.
+
+- Tactics destruct and induction now support the "with" option and the
+  "in" clause option. If the option "in" is used, an equality is added
+  to remember the term to which the induction or case analysis applied
+  (possible source of parsing incompatibilities when destruct or induction is
+  part of a let-in expression in Ltac; extra parentheses are then required).
+
+- New support for "as" clause in tactics "apply in" and "eapply in".
+
+- Some new intro patterns:
+
+  * intro pattern "?A" genererates a fresh name based on A.
+    Caveat about a slight loss of compatibility:
+    Some intro patterns don't need space between them. In particular
+    intros ?a?b used to be legal and equivalent to intros ? a ? b. Now it
+    is still legal but equivalent to intros ?a ?b.
+  * intro pattern "(A & ... & Y & Z)" synonym to "(A,....,(Y,Z)))))"
+    for right-associative constructs like /\ or exists.
+
+- Several syntax extensions concerning "rewrite":
+
+  * "rewrite A,B,C" can be used to rewrite A, then B, then C. These rewrites
+    occur only on the first subgoal: in particular, side-conditions of the
+    "rewrite A" are not concerned by the "rewrite B,C".
+  * "rewrite A by tac" allows to apply tac on all side-conditions generated by
+    the "rewrite A".
+  * "rewrite A at n" allows to select occurrences to rewrite: rewrite only
+    happen at the n-th exact occurrence of the first successful matching of
+    A in the goal.
+  * "rewrite 3 A" or "rewrite 3!A" is equivalent to "rewrite A,A,A".
+  * "rewrite !A" means rewriting A as long as possible (and at least once).
+  * "rewrite 3?A" means rewriting A at most three times.
+  * "rewrite ?A" means rewriting A as long as possible (possibly never).
+  * many of the above extensions can be combined with each other.
+
+- Introduction patterns better respect the structure of context in presence of
+  missing or extra names in nested disjunction-conjunction patterns [possible
+  source of rare incompatibilities].
+
+- New syntax "rename a into b, c into d" for "rename a into b; rename c into d"
+
+- New tactics "dependent induction/destruction H [ generalizing id_1 .. id_n ]"
+  to do induction-inversion on instantiated inductive families à la BasicElim.
+
+- Tactics "apply" and "apply in" now able to reason modulo unfolding of
+  constants (possible source of incompatibility in situations where apply
+  may fail, e.g. as argument of a try or a repeat and in a ltac function);
+  versions that do not unfold are renamed into "simple apply" and
+  "simple apply in" (usable for compatibility or for automation).
+
+- Tactics "apply" and "apply in" now able to traverse conjunctions and to
+  select the first matching lemma among the components of the conjunction;
+  tactic "apply" also able to apply lemmas of conclusion an empty type.
+
+- Tactic "apply" now supports application of several lemmas in a row.
+
+- Tactics "set" and "pose" can set functions using notation "(f x1..xn := c)".
+
+- New tactic "instantiate" (without argument).
+
+- Tactic firstorder "with" and "using" options have their meaning swapped for
+  consistency with auto/eauto (source of incompatibility).
+
+- Tactic "generalize" now supports "at" options to specify occurrences
+  and "as" options to name the quantified hypotheses.
+
+- New tactic "specialize H with a" or "specialize (H a)" allows to transform
+  in-place a universally-quantified hypothesis (H : forall x, T x) into its
+  instantiated form (H : T a). Nota: "specialize" was in fact there in earlier
+  versions of Coq, but was undocumented, and had a slightly different behavior.
+
+- New tactic "contradict H" can be used to solve any kind of goal as long as
+  the user can provide afterwards a proof of the negation of the hypothesis H.
+  If H is already a negation, say ~T, then a proof of T is asked.
+  If the current goal is a negation, say ~U, then U is saved in H afterwards,
+  hence this new tactic "contradict" extends earlier tactic "swap", which is
+  now obsolete.
+
+- Tactics f_equal is now done in ML instead of Ltac: it now works on any
+  equality of functions, regardless of the arity of the function.
+
+- New options "before id", "at top", "at bottom" for tactics "move"/"intro".
+
+- Some more debug of reflexive omega (``romega``), and internal clarifications.
+  Moreover, romega now has a variant ``romega with *`` that can be also used
+  on non-Z goals (nat, N, positive) via a call to a translation tactic named
+  zify (its purpose is to Z-ify your goal...). This zify may also be used
+  independently of romega.
+
+- Tactic "remember" now supports an "in" clause to remember only selected
+  occurrences of a term.
+
+- Tactic "pose proof" supports name overwriting in case of specialization of an
+  hypothesis.
+
+- Semi-decision tactic "jp" for first-order intuitionistic logic moved to user
+  contributions (subsumed by "firstorder").
+
+Program
+
+- Moved useful tactics in theories/Program and documented them.
+- Add Program.Basics which contains standard definitions for functional
+  programming (id, apply, flip...)
+- More robust obligation handling, dependent pattern-matching and
+  well-founded definitions.
+- New syntax " dest term as pat in term " for destructing objects using
+  an irrefutable pattern while keeping equalities (use this instead of
+  "let" in Programs).
+- Program CoFixpoint is accepted, Program Fixpoint uses the new way to infer
+  which argument decreases structurally.
+- Program Lemma, Axiom etc... now permit to have obligations in the statement
+  iff they can be automatically solved by the default tactic.
+- Renamed "Obligations Tactic" command to "Obligation Tactic".
+- New command "Preterm [ of id ]" to see the actual term fed to Coq for
+  debugging purposes.
+- New option "Transparent Obligations" to control the declaration of
+  obligations as transparent or opaque. All obligations are now transparent
+  by default, otherwise the system declares them opaque if possible.
+- Changed the notations "left" and "right" to "in_left" and "in_right" to hide
+  the proofs in standard disjunctions, to avoid breaking existing scripts when
+  importing Program. Also, put them in program_scope.
+
+Type Classes
+
+- New "Class", "Instance" and "Program Instance" commands to define
+  classes and instances documented in the reference manual.
+- New binding construct " [ Class_1 param_1 .. param_n, Class_2 ... ] "
+  for binding type classes, usable everywhere.
+- New command " Print Classes " and " Print Instances some_class " to
+  print tables for typeclasses.
+- New default eauto hint database "typeclass_instances" used by the default
+  typeclass instance search tactic.
+- New theories directory "theories/Classes" for standard typeclasses
+  declarations. Module Classes.RelationClasses is a typeclass port of
+  Relation_Definitions plus a generic development of algebra on
+  n-ary heterogeneous predicates.
+
+Setoid rewriting
+
+- Complete (and still experimental) rewrite of the tactic
+  based on typeclasses. The old interface and semantics are
+  almost entirely respected, except:
+
+  + Import Setoid is now mandatory to be able to call setoid_replace
+    and declare morphisms.
+
+  + "-->", "++>" and "==>" are now right associative notations
+    declared at level 55 in scope signature_scope.
+    Their introduction may break existing scripts that defined
+    them as notations with different levels.
+
+  + One needs to use [Typeclasses unfold [cst]] if [cst] is used
+    as an abbreviation hiding products in types of morphisms,
+    e.g. if ones redefines [relation] and declares morphisms
+    whose type mentions [relation].
+
+  + The [setoid_rewrite]'s semantics change when rewriting with
+    a lemma: it can rewrite two different instantiations of the lemma
+    at once. Use [setoid_rewrite H at 1] for (almost) the usual semantics.
+    [setoid_rewrite] will also try to rewrite under binders now, and can
+    succeed on different terms than before. In particular, it will unify under
+    let-bound variables. When called through [rewrite], the semantics are
+    unchanged though.
+
+  + [Add Morphism term : id] has different semantics when used with
+    parametric morphism: it will try to find a relation on the parameters
+    too. The behavior has also changed with respect to default relations:
+    the most recently declared Setoid/Relation will be used, the documentation
+    explains how to customize this behavior.
+
+  + Parametric Relation and Morphism are declared differently, using the
+    new [Add Parametric] commands, documented in the manual.
+
+  + Setoid_Theory is now an alias to Equivalence, scripts building objects
+    of type Setoid_Theory need to unfold (or "red") the definitions
+    of Reflexive, Symmetric and Transitive in order to get the same goals
+    as before. Scripts which introduced variables explicitely will not break.
+
+  + The order of subgoals when doing [setoid_rewrite] with side-conditions
+    is always the same: first the new goal, then the conditions.
+
+- New standard library modules ``Classes.Morphisms`` declares
+  standard morphisms on ``refl`` / ``sym`` / ``trans`` relations.
+  ``Classes.Morphisms_Prop`` declares morphisms on propositional
+  connectives and ``Classes.Morphisms_Relations`` on generalized predicate
+  connectives. ``Classes.Equivalence`` declares notations and tactics
+  related to equivalences and ``Classes.SetoidTactics`` defines the
+  setoid_replace tactics and some support for the ``Add *`` interface,
+  notably the tactic applied automatically before each ``Add Morphism``
+  proof.
+
+- User-defined subrelations are supported, as well as higher-order morphisms
+  and rewriting under binders. The tactic is also extensible entirely in Ltac.
+  The documentation has been updated to cover these features.
+
+- [setoid_rewrite] and [rewrite] now support the [at] modifier to select
+  occurrences to rewrite, and both use the [setoid_rewrite] code, even when
+  rewriting with leibniz equality if occurrences are specified.
+
+Extraction
+
+- Improved behavior of the Caml extraction of modules: name clashes should
+  not happen anymore.
+
+- The command Extract Inductive has now a syntax for infix notations. This
+  allows in particular to map Coq lists and pairs onto Caml ones:
+
+  + Extract Inductive list => list [ "[]" "(::)" ].
+  + Extract Inductive prod => "(*)" [ "(,)" ].
+
+- In pattern matchings, a default pattern "| _ -> ..." is now used whenever
+  possible if several branches are identical. For instance, functions
+  corresponding to decidability of equalities are now linear instead of
+  quadratic.
+
+- A new instruction Extraction Blacklist id1 .. idn allows to prevent filename
+  conflits with existing code, for instance when extracting module List
+  to Ocaml.
+
+CoqIDE
+
+- CoqIDE font defaults to monospace so as indentation to be meaningful.
+- CoqIDE supports nested goals and any other kind of declaration in the middle
+  of a proof.
+- Undoing non-tactic commands in CoqIDE works faster.
+- New CoqIDE menu for activating display of various implicit informations.
+- Added the possibility to choose the location of tabs in coqide:
+  (in Edit->Preferences->Misc)
+- New Open and Save As dialogs in CoqIDE which filter ``*.v`` files.
+
+Tools
+
+- New stand-alone .vo files verifier "coqchk".
+- Extended -I coqtop/coqc option to specify a logical dir: "-I dir -as coqdir".
+- New coqtop/coqc option -exclude-dir to exclude subdirs for option -R.
+- The binary "parser" has been renamed to "coq-parser".
+- Improved coqdoc and dump of globalization information to give more
+  meta-information on identifiers. All categories of Coq definitions are
+  supported, which makes typesetting trivial in the generated documentation.
+  Support for hyperlinking and indexing developments in the tex output
+  has been implemented as well.
+
+Miscellaneous
+
+- Coq installation provides enough files so that Ocaml's extensions need not
+  the Coq sources to be compiled (this assumes O'Caml 3.10 and Camlp5).
+- New commands "Set Whelp Server" and "Set Whelp Getter" to customize the
+  Whelp search tool.
+- Syntax of "Test Printing Let ref" and "Test Printing If ref" changed into
+  "Test Printing Let for ref" and "Test Printing If for ref".
+- An overhauled build system (new Makefiles); see dev/doc/build-system.txt.
+- Add -browser option to configure script.
+- Build a shared library for the C part of Coq, and use it by default on
+  non-(Windows or MacOS) systems. Bytecode executables are now pure. The
+  behaviour is configurable with -coqrunbyteflags, -coqtoolsbyteflags and
+  -custom configure options.
+- Complexity tests can be skipped by setting the environment variable
+  COQTEST_SKIPCOMPLEXITY.
+
 Version 8.1
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 Coq version 8.1 adds various new functionalities.
 
 Benjamin Grégoire implemented an alternative algorithm to check the
@@ -1059,9 +3998,303 @@ and Yale University.
 | Hugo Herbelin
 |
 
+Details of changes in 8.1beta
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Logic
+
+- Added sort-polymorphism on inductive families
+- Allowance for recursively non uniform parameters in inductive types
+
+Syntax
+
+- No more support for version 7 syntax and for translation to version 8 syntax.
+- In fixpoints, the { struct ... } annotation is not mandatory any more when
+  only one of the arguments has an inductive type
+- Added disjunctive patterns in match-with patterns
+- Support for primitive interpretation of string literals
+- Extended support for Unicode ranges
+
+Vernacular commands
+
+- Added "Print Ltac qualid" to print a user defined tactic.
+- Added "Print Rewrite HintDb" to print the content of a DB used by
+  autorewrite.
+- Added "Print Canonical Projections".
+- Added "Example" as synonym of "Definition".
+- Added "Proposition" and "Corollary" as extra synonyms of "Lemma".
+- New command "Whelp" to send requests to the Helm database of proofs
+  formalized in the Calculus of Inductive Constructions.
+- Command "functional induction" has been re-implemented from the new
+  "Function" command.
+
+Ltac and tactic syntactic extensions
+
+- New primitive "external" for communication with tool external to Coq
+- New semantics for "match t with": if a clause returns a
+  tactic, it is now applied to the current goal. If it fails, the next
+  clause or next matching subterm is tried (i.e. it behaves as "match
+  goal with" does). The keyword "lazymatch" can be used to delay the
+  evaluation of tactics occurring in matching clauses.
+- Hint base names can be parametric in auto and trivial.
+- Occurrence values can be parametric in unfold, pattern, etc.
+- Added entry constr_may_eval for tactic extensions.
+- Low-priority term printer made available in ML-written tactic extensions.
+- "Tactic Notation" extended to allow notations of tacticals.
+
+Tactics
+
+- New implementation and generalization of ``setoid_*`` (``setoid_rewrite``,
+  ``setoid_symmetry``, ``setoid_transitivity``, ``setoid_reflexivity`` and ``autorewite``).
+  New syntax for declaring relations and morphisms (old syntax still working
+  with minor modifications, but deprecated).
+
+- New implementation (still experimental) of the ring tactic with a built-in
+  notion of coefficients and a better usage of setoids.
+
+- New conversion tactic "vm_compute": evaluates the goal (or an hypothesis)
+  with a call-by-value strategy, using the compiled version of terms.
+
+- When rewriting H where H is not directly a Coq equality, search first H for
+  a registered setoid equality before starting to reduce in H. This is unlikely
+  to break any script. Should this happen nonetheless, one can insert manually
+  some "unfold ... in H" before rewriting.
+
+- Fixed various bugs about (setoid) rewrite ... in ... (in particular bug #5941)
+
+- "rewrite ... in" now accepts a clause as place where to rewrite instead of
+  just a simple hypothesis name. For instance:
+  ``rewrite H in H1,H2 |- *`` means ``rewrite H in H1; rewrite H in H2; rewrite H``
+  ``rewrite H in * |-``  will do try ``rewrite H in Hi`` for all hypothesis Hi <> H.
+
+- Added "dependent rewrite term" and "dependent rewrite term in hyp".
+
+- Added "autorewrite with ... in hyp [using ...]".
+
+- Tactic "replace" now accepts a "by" tactic clause.
+
+- Added "clear - id" to clear all hypotheses except the ones depending in id.
+
+- The argument of Declare Left Step and Declare Right Step is now a term
+  (it used to be a reference).
+
+- Omega now handles arbitrary precision integers.
+
+- Several bug fixes in Reflexive Omega (romega).
+
+- Idtac can now be left implicit in a [...|...] construct: for instance,
+  [ foo | | bar ] stands for [ foo | idtac | bar ].
+
+- Fixed a "fold" bug (non critical but possible source of incompatibilities).
+
+- Added classical_left and classical_right which transforms ``|- A \/ B`` into
+  ``~B |- A`` and ``~A |- B`` respectively.
+
+- Added command "Declare Implicit Tactic" to set up a default tactic to be
+  used to solve unresolved subterms of term arguments of tactics.
+
+- Better support for coercions to Sortclass in tactics expecting type
+  arguments.
+
+- Tactic "assert" now accepts "as" intro patterns and "by" tactic clauses.
+
+- New tactic "pose proof" that generalizes "assert (id:=p)" with intro patterns.
+
+- New introduction pattern "?" for letting Coq choose a name.
+
+- Introduction patterns now support side hypotheses (e.g. intros [|] on
+  "(nat -> nat) -> nat" works).
+
+- New introduction patterns "->" and "<-" for immediate rewriting of
+  introduced hypotheses.
+
+- Introduction patterns coming after non trivial introduction patterns now
+  force full introduction of the first pattern (e.g. ``intros [[|] p]`` on
+  ``nat->nat->nat`` now behaves like ``intros [[|?] p]``)
+
+- Added "eassumption".
+
+- Added option 'using lemmas' to auto, trivial and eauto.
+
+- Tactic "congruence" is now complete for its intended scope (ground
+  equalities and inequalities with constructors). Furthermore, it
+  tries to equates goal and hypotheses.
+
+- New tactic "rtauto" solves pure propositional logic and gives a
+  reflective version of the available proof.
+
+- Numbering of "pattern", "unfold", "simpl", ... occurrences in "match
+  with" made consistent with the printing of the return clause after
+  the term to match in the "match-with" construct (use "Set Printing All"
+  to see hidden occurrences).
+
+- Generalization of induction "induction x1...xn using scheme" where
+  scheme is an induction principle with complex predicates (like the
+  ones generated by function induction).
+
+- Some small Ltac tactics has been added to the standard library
+  (file Tactics.v):
+
+  * f_equal : instead of using the different f_equalX lemmas
+  * case_eq : a "case" without loss of information. An equality
+    stating the current situation is generated in every sub-cases.
+  * swap : for a negated goal ~B and a negated hypothesis H:~A,
+    swap H asks you to prove A from hypothesis B
+  * revert : revert H is generalize H; clear H.
+
+Extraction
+
+- All type parts should now disappear instead of sometimes producing _
+  (for instance in Map.empty).
+- Haskell extraction: types of functions are now printed, better
+  unsafeCoerce mechanism, both for hugs and ghc.
+- Scheme extraction improved, see http://www.pps.jussieu.fr/~letouzey/scheme.
+- Many bug fixes.
+
+Modules
+
+- Added "Locate Module qualid" to get the full path of a module.
+- Module/Declare Module syntax made more uniform.
+- Added syntactic sugar "Declare Module Export/Import" and
+  "Module Export/Import".
+- Added syntactic sugar "Module M(Export/Import X Y: T)" and
+  "Module Type M(Export/Import X Y: T)"
+  (only for interactive definitions)
+- Construct "with" generalized to module paths:
+  T with (Definition|Module) M1.M2....Mn.l := l'.
+
+Notations
+
+- Option "format" aware of recursive notations.
+- Added insertion of spaces by default in recursive notations w/o separators.
+- No more automatic printing box in case of user-provided printing "format".
+- New notation "exists! x:A, P" for unique existence.
+- Notations for specific numerals now compatible with generic notations of
+  numerals (e.g. "1" can be used to denote the unit of a group without
+  hiding 1%nat)
+
+Libraries
+
+- New library on String and Ascii characters (contributed by L. Thery).
+- New library FSets+FMaps of finite sets and maps.
+- New library QArith on rational numbers.
+- Small extension of Zmin.V, new Zmax.v, new Zminmax.v.
+- Reworking and extension of the files on classical logic and
+  description principles (possible incompatibilities)
+- Few other improvements in ZArith potentially exceptionally breaking the
+  compatibility (useless hypothesys of Zgt_square_simpl and
+  Zlt_square_simpl removed; fixed names mentioning letter O instead of
+  digit 0; weaken premises in Z_lt_induction).
+- Restructuration of Eqdep_dec.v and Eqdep.v: more lemmas in Type.
+- Znumtheory now contains a gcd function that can compute within Coq.
+- More lemmas stated on Type in Wf.v, removal of redundant Acc_iter and
+  Acc_iter2.
+- Change of the internal names of lemmas in OmegaLemmas.
+- Acc in Wf.v and clos_refl_trans in Relation_Operators.v now rely on
+  the allowance for recursively non uniform parameters (possible
+  source of incompatibilities: explicit pattern-matching on these
+  types may require to remove the occurrence associated to their
+  recursively non uniform parameter).
+- Coq.List.In_dec has been set transparent (this may exceptionally break
+  proof scripts, set it locally opaque for compatibility).
+- More on permutations of lists in List.v and Permutation.v.
+- List.v has been much expanded.
+- New file SetoidList.v now contains results about lists seen with
+  respect to a setoid equality.
+- Library NArith has been expanded, mostly with results coming from
+  Intmap (for instance a bitwise xor), plus also a bridge between N and
+  Bitvector.
+- Intmap has been reorganized. In particular its address type "addr" is
+  now N. User contributions known to use Intmap have been adapted
+  accordingly. If you're using this library please contact us.
+  A wrapper FMapIntMap now presents Intmap as a particular implementation
+  of FMaps. New developments are strongly encouraged to use either this
+  wrapper or any other implementations of FMap instead of using directly
+  this obsolete Intmap.
+
+Tools
+
+- New semantics for coqtop options ("-batch" expects option "-top dir"
+  for loading vernac file that contains definitions).
+- Tool coq_makefile now removes custom targets that are file names in
+  "make clean"
+- New environment variable COQREMOTEBROWSER to set the command invoked
+  to start the remote browser both in Coq and coqide. Standard syntax:
+  "%s" is the placeholder for the URL.
+
+Details of changes in 8.1gamma
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Syntax
+
+- changed parsing precedence of let/in and fun constructions of Ltac:
+  let x := t in e1; e2 is now parsed as let x := t in (e1;e2).
+
+Language and commands
+
+- Added sort-polymorphism for definitions in Type (but finally abandonned).
+- Support for implicit arguments in the types of parameters in
+  (co-)fixpoints and (co-)inductive declarations.
+- Improved type inference: use as much of possible general information.
+  before applying irreversible unification heuristics (allow e.g. to
+  infer the predicate in "(exist _ 0 (refl_equal 0) : {n:nat | n=0 })").
+- Support for Miller-Pfenning's patterns unification in type synthesis
+  (e.g. can infer P such that P x y = phi(x,y)).
+- Support for "where" clause in cofixpoint definitions.
+- New option "Set Printing Universes" for making Type levels explicit.
+
+Tactics
+
+- Improved implementation of the ring and field tactics. For compatibility
+  reasons, the previous tactics are renamed as legacy ring and legacy field,
+  but should be considered as deprecated.
+- New declarative mathematical proof language.
+- Support for argument lists of arbitrary length in Tactic Notation.
+- ``rewrite ... in H`` now fails if ``H`` is used either in an hypothesis
+  or in the goal.
+- The semantics of ``rewrite ... in *`` has been slightly modified (see doc).
+- Support for ``as`` clause in tactic injection.
+- New forward-reasoning tactic "apply in".
+- Ltac fresh operator now builds names from a concatenation of its arguments.
+- New ltac tactic "remember" to abstract over a subterm and keep an equality
+- Support for Miller-Pfenning's patterns unification in apply/rewrite/...
+  (may lead to few incompatibilities - generally now useless tactic calls).
+
+Bug fixes
+
+- Fix for notations involving basic "match" expressions.
+- Numerous other bugs solved (a few fixes may lead to incompatibilities).
+
+Details of changes in 8.1
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Bug fixes
+
+- Many bugs have been fixed (cf coq-bugs web page)
+
+Tactics
+
+- New tactics ring, ring_simplify and new tactic field now able to manage
+  power to a positive integer constant. Tactic ring on Z and R, and
+  field on R manage power (may lead to incompatibilities with V8.1gamma).
+- Tactic field_simplify now applicable in hypotheses.
+- New field_simplify_eq for simplifying field equations into ring equations.
+- Tactics ring, ring_simplify, field, field_simplify and field_simplify_eq
+  all able to apply user-given equations to rewrite monoms on the fly
+  (see documentation).
+
+Libraries
+
+- New file ConstructiveEpsilon.v defining an epsilon operator and
+  proving the axiom of choice constructively for a countable domain
+  and a decidable predicate.
+
 Version 8.0
 -----------
 
+Summary of changes
+~~~~~~~~~~~~~~~~~~
+
 Coq version 8 is a major revision of the |Coq| proof assistant. First, the
 underlying logic is slightly different. The so-called *impredicativity*
 of the sort Set has been dropped. The main reason is that it is
@@ -1160,3 +4393,300 @@ under the responsibility of Christine Paulin.
 | Hugo Herbelin & Christine Paulin
 | (updated Apr. 2006)
 |
+
+Details of changes in 8.0beta old syntax
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Logic
+
+- Set now predicative by default
+- New option -impredicative-set to set Set impredicative
+- The standard library doesn't need impredicativity of Set and is
+  compatible with the classical axioms which contradict Set impredicativity
+
+Syntax for arithmetic
+
+- Notation "=" and "<>" in Z and R are no longer implicitly in Z or R
+  (with possible introduction of a coercion), use <Z>...=... or
+  <Z>...<>... instead
+- Locate applied to a simple string (e.g. "+") searches for all
+  notations containing this string
+
+Vernacular commands
+
+- "Declare ML Module" now allows to import .cma files. This avoids to use a
+  bunch of "Declare ML Module" statements when using several ML files.
+- "Set Printing Width n" added, allows to change the size of width printing.
+- "Implicit Variables Type x,y:t" (new syntax: "Implicit Types x y:t")
+  assigns default types for binding variables.
+- Declarations of Hints and Notation now accept a "Local" flag not to
+  be exported outside the current file even if not in section
+- "Print Scopes" prints all notations
+- New command "About name" for light printing of type, implicit arguments, etc.
+- New command "Admitted" to declare incompletely proven statement as axioms
+- New keyword "Conjecture" to declare an axiom intended to be provable
+- SearchAbout can now search for lemmas referring to more than one constant
+  and on substrings of the name of the lemma
+- "Print Implicit" displays the implicit arguments of a constant
+- Locate now searches for all names having a given suffix
+- New command "Functional Scheme" for building an induction principle
+  from a function defined by case analysis and fix.
+
+Commands
+
+- new coqtop/coqc option -dont-load-proofs not to load opaque proofs in memory
+
+Implicit arguments
+
+- Inductive in sections declared with implicits now "discharged" with
+  implicits (like constants and variables)
+- Implicit Arguments flags are now synchronous with reset
+- New switch "Unset/Set Printing Implicits" (new syntax: "Unset/Set Printing
+  Implicit") to globally control printing of implicits
+
+Grammar extensions
+
+- Many newly supported UTF-8 encoded unicode blocks
+  - Greek letters (0380-03FF), Hebrew letters (U05D0-05EF), letter-like
+  symbols (2100-214F, that includes double N,Z,Q,R), prime
+  signs (from 2080-2089) and characters from many written languages
+  are valid in identifiers
+  - mathematical operators (2200-22FF), supplemental mathematical
+  operators (2A00-2AFF), miscellaneous technical (2300-23FF that
+  includes sqrt symbol), miscellaneous symbols (2600-26FF), arrows
+  (2190-21FF and 2900-297F), invisible mathematical operators (from
+  2080-2089), ... are valid symbols
+
+Library
+
+- New file about the factorial function in Arith
+
+- An additional elimination Acc_iter for Acc, simplier than Acc_rect.
+  This new elimination principle is used for definition well_founded_induction.
+
+- New library NArith on binary natural numbers
+
+- R is now of type Set
+
+- Restructuration in ZArith library
+
+  + "true_sub" used in Zplus now a definition, not a local one (source
+    of incompatibilities in proof referring to true_sub, may need extra Unfold)
+  + Some lemmas about minus moved from fast_integer to Arith/Minus.v
+    (le_minus, lt_mult_left) (theoretical source of incompatibilities)
+  + Several lemmas moved from auxiliary.v and zarith_aux.v to
+    fast_integer.v (theoretical source of incompatibilities)
+  + Variables names of iff_trans changed (source of incompatibilities)
+  + ZArith lemmas named ``OMEGA`` something or ``fast_`` something, and lemma ``new_var``
+    are now out of ZArith (except ``OMEGA2``)
+  + Redundant ZArith lemmas have been renamed: for the following pairs,
+    use the second name (Zle_Zmult_right2, Zle_mult_simpl), (OMEGA2,
+    Zle_0_plus), (Zplus_assoc_l, Zplus_assoc), (Zmult_one, Zmult_1_n),
+    (Zmult_assoc_l, Zmult_assoc), (Zmult_minus_distr, Zmult_Zminus_distr_l)
+    (add_un_double_moins_un_xO, is_double_moins_un),
+    (Rlt_monotony_rev,Rlt_monotony_contra) (source of incompatibilities)
+
+- Few minor changes (no more implicit arguments in
+  Zmult_Zminus_distr_l and Zmult_Zminus_distr_r, lemmas moved from
+  Zcomplements to other files) (rare source of incompatibilities)
+
+- New lemmas provided by users added
+
+Tactic language
+
+- Fail tactic now accepts a failure message
+- Idtac tactic now accepts a message
+- New primitive tactic "FreshId" (new syntax: "fresh") to generate new names
+- Debugger prints levels of calls
+
+Tactics
+
+- Replace can now replace proofs also
+- Fail levels are now decremented at "Match Context" blocks only and
+  if the right-hand-side of "Match term With" are tactics, these
+  tactics are never evaluated immediately and do not induce
+  backtracking (in contrast with "Match Context")
+- Quantified names now avoid global names of the current module (like
+  Intro names did) [source of rare incompatibilities: 2 changes in the set of
+  user contribs]
+- NewDestruct/NewInduction accepts intro patterns as introduction names
+- NewDestruct/NewInduction now work for non-inductive type using option "using"
+- A NewInduction naming bug for inductive types with functional
+  arguments (e.g. the accessibility predicate) has been fixed (source
+  of incompatibilities)
+- Symmetry now applies to hypotheses too
+- Inversion now accept option "as [ ... ]" to name the hypotheses
+- Contradiction now looks also for contradictory hypotheses stating ~A and A
+  (source of incompatibility)
+- "Contradiction c" try to find an hypothesis in context which
+  contradicts the type of c
+- Ring applies to new library NArith (require file NArithRing)
+- Field now works on types in Set
+- Auto with reals now try to replace le by ge (Rge_le is no longer an
+  immediate hint), resulting in shorter proofs
+- Instantiate now works in hyps (syntax : Instantiate in ...)
+- Some new tactics : EConstructor, ELeft, Eright, ESplit, EExists
+- New tactic "functional induction" to perform case analysis and
+  induction following the definition of a function.
+- Clear now fails when trying to remove a local definition used by
+  a constant appearing in the current goal
+
+Extraction (See details in plugins/extraction/CHANGES)
+
+- The old commands: 	(Recursive) Extraction Module M.
+  are now:              (Recursive) Extraction Library M.
+  To use these commands, M should come from a library M.v
+- The other syntax Extraction & Recursive Extraction now accept
+  module names as arguments.
+
+Bugs
+
+- see coq-bugs server for the complete list of fixed bugs
+
+Miscellaneous
+
+- Implicit parameters of inductive types definition now taken into
+  account for infering other implicit arguments
+
+Incompatibilities
+
+- Persistence of true_sub (4 incompatibilities in Coq user contributions)
+- Variable names of some constants changed for a better uniformity (2 changes
+  in Coq user contributions)
+- Naming of quantified names in goal now avoid global names (2 occurrences)
+- NewInduction naming for inductive types with functional arguments
+  (no incompatibility in Coq user contributions)
+- Contradiction now solve more goals (source of 2 incompatibilities)
+- Merge of eq and eqT may exceptionally result in subgoals now
+  solved automatically
+- Redundant pairs of ZArith lemmas may have different names: it may
+  cause "Apply/Rewrite with" to fail if using the first name of a pair
+  of redundant lemmas (this is solved by renaming the variables bound by
+  "with"; 3 incompatibilities in Coq user contribs)
+- ML programs referring to constants from fast_integer.v must use
+  "Coqlib.gen_constant_modules Coqlib.zarith_base_modules" instead
+
+Details of changes in 8.0beta new syntax
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+New concrete syntax
+
+- A completely new syntax for terms
+- A more uniform syntax for tactics and the tactic language
+- A few syntactic changes for vernacular commands
+- A smart automatic translator translating V8.0 files in old syntax to
+  files valid for V8.0
+
+Syntax extensions
+
+- "Grammar" for terms disappears
+- "Grammar" for tactics becomes "Tactic Notation"
+- "Syntax" disappears
+- Introduction of a notion of interpretation scope allowing to use the
+  same notations in various contexts without using specific delimiters
+  (e.g the same expression "4<=3+x" is interpreted either in "nat",
+  "positive", "N" (previously "entier"), "Z", "R", depending on which
+  interpretation scope is currently open) [see documentation for details]
+- Notation now mandatorily requires a precedence and associativity
+  (default was to set precedence to 1 and associativity to none)
+
+Revision of the standard library
+
+- Many lemmas and definitions names have been made more uniform mostly
+  in Arith, NArith, ZArith and Reals (e.g : "times" -> "Pmult",
+  "times_sym" -> "Pmult_comm", "Zle_Zmult_pos_right" ->
+  "Zmult_le_compat_r", "SUPERIEUR" -> "Gt", "ZERO" -> "Z0")
+- Order and names of arguments of basic lemmas on nat, Z, positive and R
+  have been made uniform.
+- Notions of Coq initial state are declared with (strict) implicit arguments
+- eq merged with eqT: old eq disappear, new eq (written =) is old eqT
+  and new eqT is syntactic sugar for new eq (notation == is an alias
+  for = and is written as it, exceptional source of incompatibilities)
+- Similarly, ex, ex2, all, identity are merged with exT, exT2, allT, identityT
+- Arithmetical notations for nat, positive, N, Z, R, without needing
+  any backquote or double-backquotes delimiters.
+- In Lists: new concrete notations; argument of nil is now implicit
+- All changes in the library are taken in charge by the translator
+
+Semantical changes during translation
+
+- Recursive keyword set by default (and no longer needed) in Tactic Definition
+- Set Implicit Arguments is strict by default in new syntax
+- reductions in hypotheses of the form "... in H" now apply to the type
+  also if H is a local definition
+- etc
+
+Gallina
+
+- New syntax of the form "Inductive bool : Set := true, false : bool." for
+  enumerated types
+- Experimental syntax of the form p.(fst) for record projections
+  (activable with option "Set Printing Projections" which is
+  recognized by the translator)
+
+Known problems of the automatic translation
+
+- iso-latin-1 characters are no longer supported: move your files to
+  7-bits ASCII or unicode before translation (swith to unicode is
+  automatically done if a file is loaded and saved again by coqide)
+- Renaming in ZArith: incompatibilities in Coq user contribs due to
+  merging names INZ, from Reals, and inject_nat.
+- Renaming and new lemmas in ZArith: may clash with names used by users
+- Restructuration of ZArith: replace requirement of specific modules
+  in ZArith by "Require Import ZArith_base" or "Require Import ZArith"
+- Some implicit arguments must be made explicit before translation: typically
+  for "length nil", the implicit argument of length must be made explicit
+- Grammar rules, Infix notations and V7.4 Notations must be updated wrt the
+  new scheme for syntactic extensions (see translator documentation)
+- Unsafe for annotation Cases when constructors coercions are used or when
+  annotations are eta-reduced predicates
+
+Details of changes in 8.0
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Vernacular commands
+
+- New option "Set Printing All" to deactivate all high-level forms of
+  printing (implicit arguments, coercions, destructing let,
+  if-then-else, notations, projections)
+- "Functional Scheme" and "Functional Induction" extended to polymorphic
+  types and dependent types
+- Notation now allows recursive patterns, hence recovering parts of the
+  fonctionalities of pre-V8 Grammar/Syntax commands
+- Command "Print." discontinued.
+- Redundant syntax "Implicit Arguments On/Off" discontinued
+
+New syntax
+
+- Semantics change of the if-then-else construction in new syntax:
+  "if c then t1 else t2" now stands for
+  "match c with c1 _ ... _ => t1 | c2 _ ... _ => t2 end"
+  with no dependency of t1 and t2 in the arguments of the constructors;
+  this may cause incompatibilities for files translated using coq 8.0beta
+
+Interpretation scopes
+
+- Delimiting key %bool for bool_scope added
+- Import no more needed to activate argument scopes from a module
+
+Tactics and the tactic Language
+
+- Semantics of "assert" is now consistent with the reference manual
+- New tactics stepl and stepr for chaining transitivity steps
+- Tactic "replace ... with ... in" added
+- Intro patterns now supported in Ltac (parsed with prefix "ipattern:")
+
+Executables and tools
+
+- Added option -top to change the name of the toplevel module "Top"
+- Coqdoc updated to new syntax and now part of Coq sources
+- XML exportation tool now exports the structure of vernacular files
+  (cf chapter 13 in the reference manual)
+
+User contributions
+
+- User contributions have been updated to the new syntax
+
+Bug fixes
+
+- Many bugs have been fixed (cf coq-bugs web page)
diff --git a/doc/sphinx/history.rst b/doc/sphinx/history.rst
index c21406025b..0f5b991ba4 100644
--- a/doc/sphinx/history.rst
+++ b/doc/sphinx/history.rst
@@ -721,8 +721,8 @@ J.-F. Monin from France Telecom R & D.
 | Hugo Herbelin & Christine Paulin
 |
 
-Changes in 7.0 and 7.1
-~~~~~~~~~~~~~~~~~~~~~~
+Details of changes in 7.0 and 7.1
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Notes:
 
@@ -1106,8 +1106,8 @@ New user contributions
   [Stalmarck] (Laurent Théry, Pierre Letouzey, Sophia-Antipolis)
 
 
-Changes in 7.2
-~~~~~~~~~~~~~~
+Details of changes in 7.2
+~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Language
 
@@ -1174,8 +1174,8 @@ Incompatibilities
 - New behaviour of Intuition/Tauto may exceptionally lead to incompatibilities
 
 
-Changes in 7.3
-~~~~~~~~~~~~~~
+Details of changes in 7.3
+~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Language
 
@@ -1286,8 +1286,8 @@ Misc
     LetTac (#1402)
 
 
-Changes in 7.4
-~~~~~~~~~~~~~~
+Details of changes in 7.4
+~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Symbolic notations