Fix race condition triggered by fresh universe generation

Remote counters were trying to build universe levels (as opposed to
simple integers), but did not have access to the right dirpath at
construction time. We fix it by constructing the level only at use time,
and we introduce some abstractions for qualified and unqualified level
names.

2 files changed, 10 insertions, 17 deletions

diff --git a/library/nametab.ml b/library/nametab.ml
index e29c7b2960..ab69da3467 100644
--- a/library/nametab.ml
+++ b/library/nametab.ml
@@ -347,12 +347,10 @@ module DirTab = Make(DirPath')(GlobDirRef)
 type dirtab = DirTab.t
 let the_dirtab = Summary.ref ~name:"dirtab" (DirTab.empty : dirtab)
 
-type universe_id = DirPath.t * int
-
 module UnivIdEqual =
 struct
-  type t = universe_id
-  let equal (d, i) (d', i') = DirPath.equal d d' && Int.equal i i'
+  type t = Univ.Level.Qualid.t
+  let equal = Univ.Level.Qualid.equal
 end
 module UnivTab = Make(FullPath)(UnivIdEqual)
 type univtab = UnivTab.t
@@ -375,12 +373,9 @@ let the_modtyperevtab = Summary.ref ~name:"modtyperevtab" (MPmap.empty : mptrevt
 
 module UnivIdOrdered =
 struct
-  type t = universe_id
-  let hash (d, i) = i + DirPath.hash d
-  let compare (d, i) (d', i') =
-    let c = Int.compare i i' in
-    if Int.equal c 0 then DirPath.compare d d'
-    else c
+  type t = Univ.Level.Qualid.t
+  let hash = Univ.Level.Qualid.hash
+  let compare = Univ.Level.Qualid.compare
 end
 
 module UnivIdMap = HMap.Make(UnivIdOrdered)
diff --git a/library/nametab.mli b/library/nametab.mli
index 24af07619d..496c76d9b0 100644
--- a/library/nametab.mli
+++ b/library/nametab.mli
@@ -120,11 +120,9 @@ val push_modtype : visibility -> full_path -> ModPath.t -> unit
 val push_dir : visibility -> DirPath.t -> GlobDirRef.t -> unit
 val push_syndef : visibility -> full_path -> syndef_name -> unit
 
-type universe_id = DirPath.t * int
+module UnivIdMap : CMap.ExtS with type key = Univ.Level.Qualid.t
 
-module UnivIdMap : CMap.ExtS with type key = universe_id
-
-val push_universe : visibility -> full_path -> universe_id -> unit
+val push_universe : visibility -> full_path -> Univ.Level.Qualid.t -> unit
 
 (** {6 The following functions perform globalization of qualified names } *)
 
@@ -139,7 +137,7 @@ val locate_modtype : qualid -> ModPath.t
 val locate_dir : qualid -> GlobDirRef.t
 val locate_module : qualid -> ModPath.t
 val locate_section : qualid -> DirPath.t
-val locate_universe : qualid -> universe_id
+val locate_universe : qualid -> Univ.Level.Qualid.t
 
 (** These functions globalize user-level references into global
    references, like [locate] and co, but raise a nice error message
@@ -196,7 +194,7 @@ val path_of_modtype : ModPath.t -> full_path
 
 (** A universe_id might not be registered with a corresponding user name.
     @raise Not_found if the universe was not introduced by the user. *)
-val path_of_universe : universe_id -> full_path
+val path_of_universe : Univ.Level.Qualid.t -> full_path
 
 (** Returns in particular the dirpath or the basename of the full path
    associated to global reference *)
@@ -218,7 +216,7 @@ val shortest_qualid_of_global : ?loc:Loc.t -> Id.Set.t -> GlobRef.t -> qualid
 val shortest_qualid_of_syndef : ?loc:Loc.t -> Id.Set.t -> syndef_name -> qualid
 val shortest_qualid_of_modtype : ?loc:Loc.t -> ModPath.t -> qualid
 val shortest_qualid_of_module : ?loc:Loc.t -> ModPath.t -> qualid
-val shortest_qualid_of_universe : ?loc:Loc.t -> universe_id -> qualid
+val shortest_qualid_of_universe : ?loc:Loc.t -> Univ.Level.Qualid.t -> qualid
 
 (** Deprecated synonyms *)