Merge PR#309: Ltac as a plugin

86 files changed, 76 insertions, 22 deletions

diff --git a/.gitignore b/.gitignore
index 7434f62127..35cdf9b4e8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -122,10 +122,10 @@ g_*.ml
 ide/project_file.ml
 parsing/compat.ml
 parsing/cLexer.ml
-ltac/coretactics.ml
-ltac/extratactics.ml
-ltac/extraargs.ml
-ltac/profile_ltac_tactics.ml
+plugins/ltac/coretactics.ml
+plugins/ltac/extratactics.ml
+plugins/ltac/extraargs.ml
+plugins/ltac/profile_ltac_tactics.ml
 ide/coqide_main.ml
 plugins/ssrmatching/ssrmatching.ml
 
diff --git a/Makefile.common b/Makefile.common
index 2cf4d01695..df705034e7 100644
--- a/Makefile.common
+++ b/Makefile.common
@@ -55,14 +55,14 @@ MKDIR:=install -d
 CORESRCDIRS:=\
   config 	lib		kernel	intf	kernel/byterun	library \
   engine 	pretyping	interp	proofs	parsing 	printing \
-  tactics 	vernac		stm		toplevel 	ltac
+  tactics 	vernac		stm		toplevel
 
 PLUGINDIRS:=\
   omega		romega 		micromega 	quote \
   setoid_ring 	extraction 	fourier \
   cc 		funind 		firstorder 	derive \
   rtauto 	nsatz           syntax          decl_mode	btauto \
-  ssrmatching
+  ssrmatching	ltac
 
 SRCDIRS:=\
   $(CORESRCDIRS)  \
@@ -77,14 +77,13 @@ BYTERUN:=$(addprefix kernel/byterun/, \
   coq_fix_code.o coq_memory.o coq_values.o coq_interp.o )
 
 # LINK ORDER:
-# Beware that highparsing.cma should appear before ltac.cma
 # respecting this order is useful for developers that want to load or link
 # the libraries directly
 
 CORECMA:=lib/clib.cma lib/lib.cma kernel/kernel.cma library/library.cma \
         engine/engine.cma pretyping/pretyping.cma interp/interp.cma proofs/proofs.cma \
         parsing/parsing.cma printing/printing.cma tactics/tactics.cma vernac/vernac.cma \
-	stm/stm.cma toplevel/toplevel.cma parsing/highparsing.cma ltac/ltac.cma
+	stm/stm.cma toplevel/toplevel.cma parsing/highparsing.cma
 
 TOPLOOPCMA:=stm/proofworkertop.cma stm/tacworkertop.cma stm/queryworkertop.cma
 
@@ -120,6 +119,7 @@ OTHERSYNTAXCMO:=$(addprefix plugins/syntax/, \
         string_syntax_plugin.cmo )
 DECLMODECMO:=plugins/decl_mode/decl_mode_plugin.cmo
 DERIVECMO:=plugins/derive/derive_plugin.cmo
+LTACCMO:=plugins/ltac/ltac_plugin.cmo
 SSRMATCHINGCMO:=plugins/ssrmatching/ssrmatching_plugin.cmo
 
 PLUGINSCMO:=$(OMEGACMO) $(ROMEGACMO) $(MICROMEGACMO) $(DECLMODECMO) \
@@ -127,7 +127,7 @@ PLUGINSCMO:=$(OMEGACMO) $(ROMEGACMO) $(MICROMEGACMO) $(DECLMODECMO) \
         $(FOURIERCMO) $(EXTRACTIONCMO) \
         $(CCCMO)  $(FOCMO) $(RTAUTOCMO) $(BTAUTOCMO) \
         $(FUNINDCMO) $(NSATZCMO) $(NATSYNTAXCMO) $(OTHERSYNTAXCMO) \
-	$(DERIVECMO) $(SSRMATCHINGCMO)
+	$(DERIVECMO) $(SSRMATCHINGCMO) $(LTACCMO)
 
 ifeq ($(HASNATDYNLINK)-$(BEST),false-opt)
  STATICPLUGINS:=$(PLUGINSCMO)
diff --git a/Makefile.dev b/Makefile.dev
index 8c1812da18..ea6b8b9194 100644
--- a/Makefile.dev
+++ b/Makefile.dev
@@ -121,10 +121,9 @@ pretyping: pretyping/pretyping.cma
 highparsing: parsing/highparsing.cma
 stm: stm/stm.cma
 toplevel: toplevel/toplevel.cma
-ltac: ltac/ltac.cma
 
 .PHONY: lib kernel byterun library proofs tactics interp parsing pretyping
-.PHONY: engine highparsing stm toplevel ltac
+.PHONY: engine highparsing stm toplevel
 
 ######################
 ### 3) theories files
@@ -183,6 +182,7 @@ RTAUTOVO:=$(filter plugins/rtauto/%, $(PLUGINSVO))
 EXTRACTIONVO:=$(filter plugins/extraction/%, $(PLUGINSVO))
 CCVO:=
 DERIVEVO:=$(filter plugins/derive/%, $(PLUGINSVO))
+LTACVO:=$(filter plugins/ltac/%, $(PLUGINSVO))
 
 omega: $(OMEGAVO) $(OMEGACMO) $(ROMEGAVO) $(ROMEGACMO)
 micromega: $(MICROMEGAVO) $(MICROMEGACMO) $(CSDPCERT)
@@ -194,9 +194,10 @@ funind: $(FUNINDCMO) $(FUNINDVO)
 cc: $(CCVO) $(CCCMO)
 rtauto: $(RTAUTOVO) $(RTAUTOCMO)
 btauto: $(BTAUTOVO) $(BTAUTOCMO)
+ltac: $(LTACVO) $(LTACCMO)
 
 .PHONY: omega micromega setoid_ring nsatz extraction
-.PHONY: fourier funind cc rtauto btauto
+.PHONY: fourier funind cc rtauto btauto ltac
 
 #################################
 ### Misc other development rules
diff --git a/dev/doc/changes.txt b/dev/doc/changes.txt
index f54f3fcc8e..8d2d055908 100644
--- a/dev/doc/changes.txt
+++ b/dev/doc/changes.txt
@@ -40,6 +40,24 @@ important things:
 - Some printing functions were moved from Pptactic to Pputils
 - A part of Tacexpr has been moved to Tactypes
 
+The folder itself has been turned into a plugin. This does not change much,
+but because it is a packed plugin, it may wreak havoc for third-party plugins
+depending on any module defined in the ltac/ directory. Namely, even if
+everything looks OK at compile time, a plugin can fail to load at link time
+because it mistakenly looks for a module Foo instead of Ltac_plugin.Foo, with
+an error of the form:
+
+Error: while loading myplugin.cmxs, no implementation available for Foo.
+
+In particular, most EXTEND macros will trigger this problem even if they
+seemingly do not use any Ltac module, as their expansion do.
+
+The solution is simple, and consists in adding a statement "open Ltac_plugin"
+in each file using a Ltac module, before such a module is actually called. An
+alternative solution would be to fully qualify Ltac modules, e.g. turning any
+call to Tacinterp into Ltac_plugin.Tacinterp. Note that this solution does not
+work for EXTEND macros though.
+
 ** Error handling **
 
 - All error functions now take an optional parameter `?loc:Loc.t`. For
diff --git a/dev/ocamldebug-coq.run b/dev/ocamldebug-coq.run
index 26cfcc8ae4..3850c05fd9 100644
--- a/dev/ocamldebug-coq.run
+++ b/dev/ocamldebug-coq.run
@@ -32,6 +32,6 @@ exec $OCAMLDEBUG \
         -I $COQTOP/plugins/ring       -I $COQTOP/plugins/romega \
 	-I $COQTOP/plugins/rtauto     -I $COQTOP/plugins/setoid_ring \
         -I $COQTOP/plugins/subtac     -I $COQTOP/plugins/syntax \
-        -I $COQTOP/plugins/xml \
+        -I $COQTOP/plugins/xml        -I $COQTOP/plugins/ltac \
         -I $COQTOP/ide \
 	"$@"
diff --git a/plugins/btauto/g_btauto.ml4 b/plugins/btauto/g_btauto.ml4
index f3e2c99f4c..2980274487 100644
--- a/plugins/btauto/g_btauto.ml4
+++ b/plugins/btauto/g_btauto.ml4
@@ -8,6 +8,8 @@
 
 (*i camlp4deps: "grammar/grammar.cma"  i*)
 
+open Ltac_plugin
+
 DECLARE PLUGIN "btauto_plugin"
 
 TACTIC EXTEND btauto
diff --git a/plugins/cc/g_congruence.ml4 b/plugins/cc/g_congruence.ml4
index 6f6811334d..7e76854b16 100644
--- a/plugins/cc/g_congruence.ml4
+++ b/plugins/cc/g_congruence.ml4
@@ -8,6 +8,7 @@
 
 (*i camlp4deps: "grammar/grammar.cma" i*)
 
+open Ltac_plugin
 open Cctac
 open Stdarg
 
diff --git a/plugins/decl_mode/decl_interp.ml b/plugins/decl_mode/decl_interp.ml
index f68c01b18b..2b63ed6d6e 100644
--- a/plugins/decl_mode/decl_interp.ml
+++ b/plugins/decl_mode/decl_interp.ml
@@ -6,6 +6,7 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 
+open Ltac_plugin
 open CErrors
 open Util
 open Names
diff --git a/plugins/decl_mode/decl_proof_instr.ml b/plugins/decl_mode/decl_proof_instr.ml
index e19dc86c45..deb2ede1d5 100644
--- a/plugins/decl_mode/decl_proof_instr.ml
+++ b/plugins/decl_mode/decl_proof_instr.ml
@@ -6,6 +6,7 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 
+open Ltac_plugin
 open CErrors
 open Util
 open Pp
diff --git a/plugins/decl_mode/g_decl_mode.ml4 b/plugins/decl_mode/g_decl_mode.ml4
index 18a35c6cfb..a71d20f0dc 100644
--- a/plugins/decl_mode/g_decl_mode.ml4
+++ b/plugins/decl_mode/g_decl_mode.ml4
@@ -10,6 +10,7 @@
 
 DECLARE PLUGIN "decl_mode_plugin"
 
+open Ltac_plugin
 open Compat
 open Pp
 open Decl_expr
diff --git a/plugins/decl_mode/ppdecl_proof.ml b/plugins/decl_mode/ppdecl_proof.ml
index 59a0bb5a2d..f5de638ed2 100644
--- a/plugins/decl_mode/ppdecl_proof.ml
+++ b/plugins/decl_mode/ppdecl_proof.ml
@@ -6,6 +6,7 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 
+open Ltac_plugin
 open CErrors
 open Pp
 open Decl_expr
diff --git a/plugins/extraction/g_extraction.ml4 b/plugins/extraction/g_extraction.ml4
index e1d6bb4a84..3ed959cf2c 100644
--- a/plugins/extraction/g_extraction.ml4
+++ b/plugins/extraction/g_extraction.ml4
@@ -12,6 +12,7 @@ DECLARE PLUGIN "extraction_plugin"
 
 (* ML names *)
 
+open Ltac_plugin
 open Genarg
 open Stdarg
 open Pcoq.Prim
diff --git a/plugins/firstorder/g_ground.ml4 b/plugins/firstorder/g_ground.ml4
index 260e86ad67..e28d6aa626 100644
--- a/plugins/firstorder/g_ground.ml4
+++ b/plugins/firstorder/g_ground.ml4
@@ -8,6 +8,7 @@
 
 (*i camlp4deps: "grammar/grammar.cma"  i*)
 
+open Ltac_plugin
 open Formula
 open Sequent
 open Ground
diff --git a/plugins/firstorder/ground.ml b/plugins/firstorder/ground.ml
index 628af4e719..d6cd7e2a08 100644
--- a/plugins/firstorder/ground.ml
+++ b/plugins/firstorder/ground.ml
@@ -6,6 +6,7 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 
+open Ltac_plugin
 open Formula
 open Sequent
 open Rules
diff --git a/plugins/fourier/g_fourier.ml4 b/plugins/fourier/g_fourier.ml4
index 7c665ae7b5..1960fa8355 100644
--- a/plugins/fourier/g_fourier.ml4
+++ b/plugins/fourier/g_fourier.ml4
@@ -8,6 +8,7 @@
 
 (*i camlp4deps: "grammar/grammar.cma" i*)
 
+open Ltac_plugin
 open FourierR
 
 DECLARE PLUGIN "fourier_plugin"
diff --git a/plugins/funind/g_indfun.ml4 b/plugins/funind/g_indfun.ml4
index 6603a95a84..368b23be30 100644
--- a/plugins/funind/g_indfun.ml4
+++ b/plugins/funind/g_indfun.ml4
@@ -6,6 +6,7 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 (*i camlp4deps: "grammar/grammar.cma" i*)
+open Ltac_plugin
 open Compat
 open Util
 open Term
diff --git a/plugins/funind/invfun.ml b/plugins/funind/invfun.ml
index c8b4e48337..70333b063d 100644
--- a/plugins/funind/invfun.ml
+++ b/plugins/funind/invfun.ml
@@ -6,6 +6,7 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 
+open Ltac_plugin
 open Tacexpr
 open Declarations
 open CErrors
diff --git a/ltac/tauto.mli b/plugins/ltac/Ltac.v
index e69de29bb2..e69de29bb2 100644
--- a/ltac/tauto.mli
+++ b/plugins/ltac/Ltac.v
diff --git a/ltac/coretactics.ml4 b/plugins/ltac/coretactics.ml4
index 28ff6df838..28ff6df838 100644
--- a/ltac/coretactics.ml4
+++ b/plugins/ltac/coretactics.ml4
diff --git a/ltac/evar_tactics.ml b/plugins/ltac/evar_tactics.ml
index c5b26e6d56..c5b26e6d56 100644
--- a/ltac/evar_tactics.ml
+++ b/plugins/ltac/evar_tactics.ml
diff --git a/ltac/evar_tactics.mli b/plugins/ltac/evar_tactics.mli
index e67540c055..e67540c055 100644
--- a/ltac/evar_tactics.mli
+++ b/plugins/ltac/evar_tactics.mli
diff --git a/ltac/extraargs.ml4 b/plugins/ltac/extraargs.ml4
index 53b726432c..53b726432c 100644
--- a/ltac/extraargs.ml4
+++ b/plugins/ltac/extraargs.ml4
diff --git a/ltac/extraargs.mli b/plugins/ltac/extraargs.mli
index b12187e18a..b12187e18a 100644
--- a/ltac/extraargs.mli
+++ b/plugins/ltac/extraargs.mli
diff --git a/ltac/extratactics.ml4 b/plugins/ltac/extratactics.ml4
index 1223f6eb4b..1223f6eb4b 100644
--- a/ltac/extratactics.ml4
+++ b/plugins/ltac/extratactics.ml4
diff --git a/ltac/extratactics.mli b/plugins/ltac/extratactics.mli
index 18334dafe7..18334dafe7 100644
--- a/ltac/extratactics.mli
+++ b/plugins/ltac/extratactics.mli
diff --git a/ltac/g_auto.ml4 b/plugins/ltac/g_auto.ml4
index a37cf306e1..a37cf306e1 100644
--- a/ltac/g_auto.ml4
+++ b/plugins/ltac/g_auto.ml4
diff --git a/ltac/g_class.ml4 b/plugins/ltac/g_class.ml4
index a28132a4b0..a28132a4b0 100644
--- a/ltac/g_class.ml4
+++ b/plugins/ltac/g_class.ml4
diff --git a/ltac/g_eqdecide.ml4 b/plugins/ltac/g_eqdecide.ml4
index 905653281c..905653281c 100644
--- a/ltac/g_eqdecide.ml4
+++ b/plugins/ltac/g_eqdecide.ml4
diff --git a/ltac/g_ltac.ml4 b/plugins/ltac/g_ltac.ml4
index 54229bb2ae..54229bb2ae 100644
--- a/ltac/g_ltac.ml4
+++ b/plugins/ltac/g_ltac.ml4
diff --git a/ltac/g_obligations.ml4 b/plugins/ltac/g_obligations.ml4
index d286a58708..d286a58708 100644
--- a/ltac/g_obligations.ml4
+++ b/plugins/ltac/g_obligations.ml4
diff --git a/ltac/g_rewrite.ml4 b/plugins/ltac/g_rewrite.ml4
index b1c4f58eb8..b1c4f58eb8 100644
--- a/ltac/g_rewrite.ml4
+++ b/plugins/ltac/g_rewrite.ml4
diff --git a/ltac/g_tactic.ml4 b/plugins/ltac/g_tactic.ml4
index 685c07c9a8..685c07c9a8 100644
--- a/ltac/g_tactic.ml4
+++ b/plugins/ltac/g_tactic.ml4
diff --git a/ltac/ltac.mllib b/plugins/ltac/ltac_plugin.mlpack
index af1c7149da..af1c7149da 100644
--- a/ltac/ltac.mllib
+++ b/plugins/ltac/ltac_plugin.mlpack
diff --git a/ltac/pltac.ml b/plugins/ltac/pltac.ml
index 1d21118ae8..1d21118ae8 100644
--- a/ltac/pltac.ml
+++ b/plugins/ltac/pltac.ml
diff --git a/ltac/pltac.mli b/plugins/ltac/pltac.mli
index 810e1ec39a..810e1ec39a 100644
--- a/ltac/pltac.mli
+++ b/plugins/ltac/pltac.mli
diff --git a/ltac/pptactic.ml b/plugins/ltac/pptactic.ml
index fccee6e40a..fccee6e40a 100644
--- a/ltac/pptactic.ml
+++ b/plugins/ltac/pptactic.ml
diff --git a/ltac/pptactic.mli b/plugins/ltac/pptactic.mli
index 86e3ea5484..86e3ea5484 100644
--- a/ltac/pptactic.mli
+++ b/plugins/ltac/pptactic.mli
diff --git a/ltac/pptacticsig.mli b/plugins/ltac/pptacticsig.mli
index 74ddd377ad..74ddd377ad 100644
--- a/ltac/pptacticsig.mli
+++ b/plugins/ltac/pptacticsig.mli
diff --git a/ltac/profile_ltac.ml b/plugins/ltac/profile_ltac.ml
index 2514ededb0..2514ededb0 100644
--- a/ltac/profile_ltac.ml
+++ b/plugins/ltac/profile_ltac.ml
diff --git a/ltac/profile_ltac.mli b/plugins/ltac/profile_ltac.mli
index e5e2e41975..e5e2e41975 100644
--- a/ltac/profile_ltac.mli
+++ b/plugins/ltac/profile_ltac.mli
diff --git a/ltac/profile_ltac_tactics.ml4 b/plugins/ltac/profile_ltac_tactics.ml4
index 8cb76d81c5..8cb76d81c5 100644
--- a/ltac/profile_ltac_tactics.ml4
+++ b/plugins/ltac/profile_ltac_tactics.ml4
diff --git a/ltac/rewrite.ml b/plugins/ltac/rewrite.ml
index 3c5a109c0d..3c5a109c0d 100644
--- a/ltac/rewrite.ml
+++ b/plugins/ltac/rewrite.ml
diff --git a/ltac/rewrite.mli b/plugins/ltac/rewrite.mli
index 35c4483513..35c4483513 100644
--- a/ltac/rewrite.mli
+++ b/plugins/ltac/rewrite.mli
diff --git a/ltac/tacarg.ml b/plugins/ltac/tacarg.ml
index 42552c4846..42552c4846 100644
--- a/ltac/tacarg.ml
+++ b/plugins/ltac/tacarg.ml
diff --git a/ltac/tacarg.mli b/plugins/ltac/tacarg.mli
index bfa423db20..bfa423db20 100644
--- a/ltac/tacarg.mli
+++ b/plugins/ltac/tacarg.mli
diff --git a/ltac/taccoerce.ml b/plugins/ltac/taccoerce.ml
index df38a42cb9..df38a42cb9 100644
--- a/ltac/taccoerce.ml
+++ b/plugins/ltac/taccoerce.ml
diff --git a/ltac/taccoerce.mli b/plugins/ltac/taccoerce.mli
index 0b67f8726e..0b67f8726e 100644
--- a/ltac/taccoerce.mli
+++ b/plugins/ltac/taccoerce.mli
diff --git a/ltac/tacentries.ml b/plugins/ltac/tacentries.ml
index 2e2b55be74..2e2b55be74 100644
--- a/ltac/tacentries.ml
+++ b/plugins/ltac/tacentries.ml
diff --git a/ltac/tacentries.mli b/plugins/ltac/tacentries.mli
index 969c118fb5..969c118fb5 100644
--- a/ltac/tacentries.mli
+++ b/plugins/ltac/tacentries.mli
diff --git a/ltac/tacenv.ml b/plugins/ltac/tacenv.ml
index e3c2b4ad51..e3c2b4ad51 100644
--- a/ltac/tacenv.ml
+++ b/plugins/ltac/tacenv.ml
diff --git a/ltac/tacenv.mli b/plugins/ltac/tacenv.mli
index 94e14223aa..94e14223aa 100644
--- a/ltac/tacenv.mli
+++ b/plugins/ltac/tacenv.mli
diff --git a/ltac/tacexpr.mli b/plugins/ltac/tacexpr.mli
index 9c25a16457..9c25a16457 100644
--- a/ltac/tacexpr.mli
+++ b/plugins/ltac/tacexpr.mli
diff --git a/ltac/tacintern.ml b/plugins/ltac/tacintern.ml
index 763e0dc22e..763e0dc22e 100644
--- a/ltac/tacintern.ml
+++ b/plugins/ltac/tacintern.ml
diff --git a/ltac/tacintern.mli b/plugins/ltac/tacintern.mli
index 71ca354fa1..71ca354fa1 100644
--- a/ltac/tacintern.mli
+++ b/plugins/ltac/tacintern.mli
diff --git a/ltac/tacinterp.ml b/plugins/ltac/tacinterp.ml
index 32bcdfb6a4..32bcdfb6a4 100644
--- a/ltac/tacinterp.ml
+++ b/plugins/ltac/tacinterp.ml
diff --git a/ltac/tacinterp.mli b/plugins/ltac/tacinterp.mli
index 6f64981eff..6f64981eff 100644
--- a/ltac/tacinterp.mli
+++ b/plugins/ltac/tacinterp.mli
diff --git a/ltac/tacsubst.ml b/plugins/ltac/tacsubst.ml
index 55de583613..55de583613 100644
--- a/ltac/tacsubst.ml
+++ b/plugins/ltac/tacsubst.ml
diff --git a/ltac/tacsubst.mli b/plugins/ltac/tacsubst.mli
index c1bf272579..c1bf272579 100644
--- a/ltac/tacsubst.mli
+++ b/plugins/ltac/tacsubst.mli
diff --git a/ltac/tactic_debug.ml b/plugins/ltac/tactic_debug.ml
index 5cbddc7f64..5cbddc7f64 100644
--- a/ltac/tactic_debug.ml
+++ b/plugins/ltac/tactic_debug.ml
diff --git a/ltac/tactic_debug.mli b/plugins/ltac/tactic_debug.mli
index 520fb41eff..520fb41eff 100644
--- a/ltac/tactic_debug.mli
+++ b/plugins/ltac/tactic_debug.mli
diff --git a/ltac/tactic_matching.ml b/plugins/ltac/tactic_matching.ml
index ef45ee47e1..ef45ee47e1 100644
--- a/ltac/tactic_matching.ml
+++ b/plugins/ltac/tactic_matching.ml
diff --git a/ltac/tactic_matching.mli b/plugins/ltac/tactic_matching.mli
index 090207bcc3..090207bcc3 100644
--- a/ltac/tactic_matching.mli
+++ b/plugins/ltac/tactic_matching.mli
diff --git a/ltac/tactic_option.ml b/plugins/ltac/tactic_option.ml
index a5ba3b8371..a5ba3b8371 100644
--- a/ltac/tactic_option.ml
+++ b/plugins/ltac/tactic_option.ml
diff --git a/ltac/tactic_option.mli b/plugins/ltac/tactic_option.mli
index ed759a76db..ed759a76db 100644
--- a/ltac/tactic_option.mli
+++ b/plugins/ltac/tactic_option.mli
diff --git a/ltac/tauto.ml b/plugins/ltac/tauto.ml
index 756958c2f0..756958c2f0 100644
--- a/ltac/tauto.ml
+++ b/plugins/ltac/tauto.ml
diff --git a/plugins/ltac/tauto.mli b/plugins/ltac/tauto.mli
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/plugins/ltac/tauto.mli
diff --git a/plugins/ltac/vo.itarget b/plugins/ltac/vo.itarget
new file mode 100644
index 0000000000..a28fb770be
--- /dev/null
+++ b/plugins/ltac/vo.itarget
@@ -0,0 +1 @@
+Ltac.vo
diff --git a/plugins/micromega/g_micromega.ml4 b/plugins/micromega/g_micromega.ml4
index 79020ed037..ccb6daa116 100644
--- a/plugins/micromega/g_micromega.ml4
+++ b/plugins/micromega/g_micromega.ml4
@@ -16,6 +16,7 @@
 
 (*i camlp4deps: "grammar/grammar.cma" i*)
 
+open Ltac_plugin
 open Stdarg
 open Tacarg
 
diff --git a/plugins/nsatz/g_nsatz.ml4 b/plugins/nsatz/g_nsatz.ml4
index 5f906a8dad..195dec3627 100644
--- a/plugins/nsatz/g_nsatz.ml4
+++ b/plugins/nsatz/g_nsatz.ml4
@@ -1,5 +1,3 @@
-DECLARE PLUGIN "nsatz_plugin"
-
 (************************************************************************)
 (*  v      *   The Coq Proof Assistant  /  The Coq Development Team     *)
 (* <O___,, *   INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2016     *)
@@ -10,6 +8,8 @@ DECLARE PLUGIN "nsatz_plugin"
 
 (*i camlp4deps: "grammar/grammar.cma" i*)
 
+open Ltac_plugin
+
 DECLARE PLUGIN "nsatz_plugin"
 
 TACTIC EXTEND nsatz_compute
diff --git a/plugins/omega/g_omega.ml4 b/plugins/omega/g_omega.ml4
index 27115abecc..6b711a1761 100644
--- a/plugins/omega/g_omega.ml4
+++ b/plugins/omega/g_omega.ml4
@@ -17,6 +17,7 @@
 
 DECLARE PLUGIN "omega_plugin"
 
+open Ltac_plugin
 open Names
 open Coq_omega
 open Stdarg
diff --git a/plugins/quote/g_quote.ml4 b/plugins/quote/g_quote.ml4
index e7e6ecef98..f2c021f595 100644
--- a/plugins/quote/g_quote.ml4
+++ b/plugins/quote/g_quote.ml4
@@ -8,6 +8,7 @@
 
 (*i camlp4deps: "grammar/grammar.cma" i*)
 
+open Ltac_plugin
 open Names
 open Misctypes
 open Tacexpr
diff --git a/plugins/romega/g_romega.ml4 b/plugins/romega/g_romega.ml4
index 2f38688d1f..9a54ad7789 100644
--- a/plugins/romega/g_romega.ml4
+++ b/plugins/romega/g_romega.ml4
@@ -10,6 +10,7 @@
 
 DECLARE PLUGIN "romega_plugin"
 
+open Ltac_plugin
 open Names
 open Refl_omega
 open Stdarg
diff --git a/plugins/rtauto/g_rtauto.ml4 b/plugins/rtauto/g_rtauto.ml4
index d27b04834e..7e58ef9a3e 100644
--- a/plugins/rtauto/g_rtauto.ml4
+++ b/plugins/rtauto/g_rtauto.ml4
@@ -8,6 +8,8 @@
 
 (*i camlp4deps: "grammar/grammar.cma"  i*)
 
+open Ltac_plugin
+
 DECLARE PLUGIN "rtauto_plugin"
 
 TACTIC EXTEND rtauto
diff --git a/plugins/rtauto/refl_tauto.ml b/plugins/rtauto/refl_tauto.ml
index 367a133330..35d6768c13 100644
--- a/plugins/rtauto/refl_tauto.ml
+++ b/plugins/rtauto/refl_tauto.ml
@@ -8,6 +8,7 @@
 
 module Search = Explore.Make(Proof_search)
 
+open Ltac_plugin
 open CErrors
 open Util
 open Term
diff --git a/plugins/setoid_ring/g_newring.ml4 b/plugins/setoid_ring/g_newring.ml4
index 0987c44ae2..707ff79a6c 100644
--- a/plugins/setoid_ring/g_newring.ml4
+++ b/plugins/setoid_ring/g_newring.ml4
@@ -8,6 +8,7 @@
 
 (*i camlp4deps: "grammar/grammar.cma" i*)
 
+open Ltac_plugin
 open Pp
 open Util
 open Libnames
diff --git a/plugins/setoid_ring/newring.ml b/plugins/setoid_ring/newring.ml
index 657efe175b..59f23a6379 100644
--- a/plugins/setoid_ring/newring.ml
+++ b/plugins/setoid_ring/newring.ml
@@ -6,6 +6,7 @@
 (*         *       GNU Lesser General Public License Version 2.1        *)
 (************************************************************************)
 
+open Ltac_plugin
 open Pp
 open CErrors
 open Util
diff --git a/plugins/ssrmatching/ssrmatching.ml4 b/plugins/ssrmatching/ssrmatching.ml4
index fc988a2c5f..f4f6efa4a6 100644
--- a/plugins/ssrmatching/ssrmatching.ml4
+++ b/plugins/ssrmatching/ssrmatching.ml4
@@ -15,6 +15,7 @@ let frozen_lexer = CLexer.freeze () ;;
 (*i camlp4use: "pa_extend.cmo" i*)
 (*i camlp4deps: "grammar/grammar.cma" i*)
 
+open Ltac_plugin
 open Names
 open Pp
 open Pcoq
diff --git a/test-suite/bugs/closed/3612.v b/test-suite/bugs/closed/3612.v
index a547685070..4b4f81dbce 100644
--- a/test-suite/bugs/closed/3612.v
+++ b/test-suite/bugs/closed/3612.v
@@ -38,8 +38,11 @@ Axiom path_path_sigma : forall {A : Type} (P : A -> Type) (u v : sigT P)
            (s : transport (fun x => transport P x u.2 = v.2) r p..2 = q..2),
 p = q.
 
+Declare ML Module "ltac_plugin".
 Declare ML Module "coretactics".
 
+Set Default Proof Mode "Classic".
+
 Goal forall (A : Type) (B : forall _ : A, Type) (x : @sigT A (fun x : A => B x))
             (xx : @paths (@sigT A (fun x0 : A => B x0)) x x),
        @paths (@paths (@sigT A (fun x0 : A => B x0)) x x) xx
diff --git a/test-suite/bugs/closed/3649.v b/test-suite/bugs/closed/3649.v
index fc4c171e2c..8687eaab00 100644
--- a/test-suite/bugs/closed/3649.v
+++ b/test-suite/bugs/closed/3649.v
@@ -2,7 +2,9 @@
 (* File reduced by coq-bug-finder from original input, then from 9518 lines to 404 lines, then from 410 lines to 208 lines, then from 162 lines to 77 lines *)
 (* coqc version trunk (September 2014) compiled on Sep 18 2014 21:0:5 with OCaml 4.01.0
    coqtop version cagnode16:/afs/csail.mit.edu/u/j/jgross/coq-trunk,trunk (07e4438bd758c2ced8caf09a6961ccd77d84e42b) *)
+Declare ML Module "ltac_plugin".
 Declare ML Module "coretactics".
+Set Default Proof Mode "Classic".
 Reserved Notation "x -> y" (at level 99, right associativity, y at level 200).
 Reserved Notation "x = y" (at level 70, no associativity).
 Delimit Scope type_scope with type.
diff --git a/test-suite/bugs/closed/4121.v b/test-suite/bugs/closed/4121.v
index d34a2b8b1b..816bc845fd 100644
--- a/test-suite/bugs/closed/4121.v
+++ b/test-suite/bugs/closed/4121.v
@@ -4,6 +4,8 @@ Unset Strict Universe Declaration.
 (* coqc version 8.5beta1 (March 2015) compiled on Mar 11 2015 18:51:36 with OCaml 4.01.0
    coqtop version cagnode15:/afs/csail.mit.edu/u/j/jgross/coq-8.5,v8.5 (8dbfee5c5f897af8186cb1bdfb04fd4f88eca677) *)
 
+Declare ML Module "ltac_plugin".
+
 Set Universe Polymorphism.
 Class Contr_internal (A : Type) := BuildContr { center : A }.
 Arguments center A {_}.
@@ -13,4 +15,4 @@ Definition contr_paths_contr0 {A} `{Contr A} : Contr A := {| center := center A
 Instance contr_paths_contr1 {A} `{Contr A} : Contr A := {| center := center A |}.
 Check @contr_paths_contr0@{i}.
 Check @contr_paths_contr1@{i}. (* Error: Universe instance should have length 2 *)
-(** It should have length 1, just like contr_paths_contr0 *)
\ No newline at end of file
+(** It should have length 1, just like contr_paths_contr0 *)
diff --git a/test-suite/bugs/closed/4527.v b/test-suite/bugs/closed/4527.v
index 08628377f0..c6fcc24b6b 100644
--- a/test-suite/bugs/closed/4527.v
+++ b/test-suite/bugs/closed/4527.v
@@ -5,6 +5,7 @@ then from 269 lines to 255 lines *)
 (* coqc version 8.5 (January 2016) compiled on Jan 23 2016 16:15:22 with OCaml 
 4.01.0
    coqtop version 8.5 (January 2016) *)
+Declare ML Module "ltac_plugin".
 Inductive False := .
 Axiom proof_admitted : False.
 Tactic Notation "admit" := case proof_admitted.
diff --git a/test-suite/bugs/closed/4533.v b/test-suite/bugs/closed/4533.v
index ae17fb145d..64c7fd8eb1 100644
--- a/test-suite/bugs/closed/4533.v
+++ b/test-suite/bugs/closed/4533.v
@@ -5,6 +5,7 @@ then from 285 lines to 271 lines *)
 (* coqc version 8.5 (January 2016) compiled on Jan 23 2016 16:15:22 with OCaml 
 4.01.0
    coqtop version 8.5 (January 2016) *)
+Declare ML Module "ltac_plugin".
 Inductive False := .
 Axiom proof_admitted : False.
 Tactic Notation "admit" := case proof_admitted.
@@ -223,4 +224,4 @@ v = _) r,
     | [ |- p2 @ p0 @ p1 @ eissect (to O A) (g x) = r ] => idtac "good"
     | [ |- ?G ] => fail 1 "bad" G
     end.
-    Fail rewrite concat_p_pp.
\ No newline at end of file
+    Fail rewrite concat_p_pp.
diff --git a/test-suite/bugs/closed/4544.v b/test-suite/bugs/closed/4544.v
index da140c9318..64dd8c304f 100644
--- a/test-suite/bugs/closed/4544.v
+++ b/test-suite/bugs/closed/4544.v
@@ -2,6 +2,7 @@
 (* File reduced by coq-bug-finder from original input, then from 2553 lines to 1932 lines, then from 1946 lines to 1932 lines, then from 2467 lines to 1002 lines, then from 1016 lines to 1002 lines *)
 (* coqc version 8.5 (January 2016) compiled on Jan 23 2016 16:15:22 with OCaml 4.01.0
    coqtop version 8.5 (January 2016) *)
+Declare ML Module "ltac_plugin".
 Inductive False := .
 Axiom proof_admitted : False.
 Tactic Notation "admit" := case proof_admitted.
@@ -1004,4 +1005,4 @@ Proof.
   Fail Timeout 1 Time rewrite !loops_functor_group.
   (* 0.004 s in 8.5rc1, 8.677 s in 8.5 *)
   Timeout 1 do 3 rewrite loops_functor_group.
-Abort.
\ No newline at end of file
+Abort.
diff --git a/theories/Init/Notations.v b/theories/Init/Notations.v
index 48fbe0793c..edcd53005e 100644
--- a/theories/Init/Notations.v
+++ b/theories/Init/Notations.v
@@ -88,9 +88,12 @@ Open Scope type_scope.
 
 (** ML Tactic Notations *)
 
+Declare ML Module "ltac_plugin".
 Declare ML Module "coretactics".
 Declare ML Module "extratactics".
 Declare ML Module "g_auto".
 Declare ML Module "g_class".
 Declare ML Module "g_eqdecide".
 Declare ML Module "g_rewrite".
+
+Global Set Default Proof Mode "Classic".
diff --git a/tools/coq_makefile.ml b/tools/coq_makefile.ml
index 624b9ced7d..4842a89151 100644
--- a/tools/coq_makefile.ml
+++ b/tools/coq_makefile.ml
@@ -50,9 +50,9 @@ let section s =
 let lib_dirs =
   ["kernel"; "lib"; "library"; "parsing";
    "pretyping"; "interp"; "printing"; "intf";
-   "proofs"; "tactics"; "tools"; "ltacprof";
+   "proofs"; "tactics"; "tools";
    "vernac"; "stm"; "toplevel"; "grammar"; "config";
-   "ltac"; "engine"]
+   "engine"]
 
 
 let usage () =
diff --git a/toplevel/coqtop.ml b/toplevel/coqtop.ml
index d9f8ed8815..cc1c44fe31 100644
--- a/toplevel/coqtop.ml
+++ b/toplevel/coqtop.ml
@@ -603,8 +603,6 @@ let init_toplevel arglist =
   init_gc ();
   Sys.catch_break false; (* Ctrl-C is fatal during the initialisation *)
   Lib.init();
-  (* Default Proofb Mode starts with an alternative default. *)
-  Goptions.set_string_option_value ["Default";"Proof";"Mode"] "Classic";
   begin
     try
       let extras = parse_args arglist in