[ssreflect] Fix module scoping problems due to packing and mli files.

Unfortunately, mli-only files cannot be included in packs, so we have
the weird situation that the scope for `Tacexpr` is wrong. So we
cannot address the module as `Ltac_plugin.Tacexpr` but it lives in the
global namespace instead.

This creates problem when using other modular build/packing strategies
[such as #6857] This could be indeed considered a bug in the OCaml
compiler.

In order to remedy this situation we face two choices:
- leave the module out of the pack (!)
- create an implementation for the module

I chose the second solution as it seems to me like the most sensible
choice.

cc: #6512.

2 files changed, 12 insertions, 8 deletions

diff --git a/plugins/ssr/ssrparser.mli b/plugins/ssr/ssrparser.mli
index 130550388..2ac7c7e26 100644
--- a/plugins/ssr/ssrparser.mli
+++ b/plugins/ssr/ssrparser.mli
@@ -10,6 +10,8 @@
 
 (* This file is (C) Copyright 2006-2015 Microsoft Corporation and Inria. *)
 
+open Ltac_plugin
+
 val ssrtacarg : Tacexpr.raw_tactic_expr Pcoq.Gram.entry
 val wit_ssrtacarg : (Tacexpr.raw_tactic_expr, Tacexpr.glob_tactic_expr, Geninterp.Val.t) Genarg.genarg_type
 val pr_ssrtacarg : 'a -> 'b -> (Notation_term.tolerability -> 'c) -> 'c
diff --git a/plugins/ssr/ssrtacticals.mli b/plugins/ssr/ssrtacticals.mli
index 84b184713..a5636ad0f 100644
--- a/plugins/ssr/ssrtacticals.mli
+++ b/plugins/ssr/ssrtacticals.mli
@@ -10,21 +10,23 @@
 
 (* This file is (C) Copyright 2006-2015 Microsoft Corporation and Inria. *)
 
+open Ltac_plugin
+open Ssrmatching_plugin
 
 val tclSEQAT :
-  Ltac_plugin.Tacinterp.interp_sign ->
-  Ltac_plugin.Tacinterp.Value.t ->
+  Tacinterp.interp_sign ->
+  Tacinterp.Value.t ->
   Ssrast.ssrdir ->
   int Misctypes.or_var *
-    (('a * Ltac_plugin.Tacinterp.Value.t option list) *
-       Ltac_plugin.Tacinterp.Value.t option) ->
+    (('a * Tacinterp.Value.t option list) *
+       Tacinterp.Value.t option) ->
   Tacmach.tactic
 
 val tclCLAUSES :
   unit Proofview.tactic ->
   (Ssrast.ssrhyps *
      ((Ssrast.ssrhyp_or_id * string) *
-        Ssrmatching_plugin.Ssrmatching.cpattern option)
+        Ssrmatching.cpattern option)
        option)
     list * Ssrast.ssrclseq ->
   unit Proofview.tactic
@@ -34,12 +36,12 @@ val hinttac :
            bool -> bool * Tacinterp.Value.t option list -> Ssrast.v82tac
 
 val ssrdotac :
-  Ltac_plugin.Tacinterp.interp_sign ->
+  Tacinterp.interp_sign ->
   ((int Misctypes.or_var * Ssrast.ssrmmod) *
-     (bool * Ltac_plugin.Tacinterp.Value.t option list)) *
+     (bool * Tacinterp.Value.t option list)) *
     ((Ssrast.ssrhyps *
         ((Ssrast.ssrhyp_or_id * string) *
-           Ssrmatching_plugin.Ssrmatching.cpattern option)
+           Ssrmatching.cpattern option)
           option)
        list * Ssrast.ssrclseq) ->
   Goal.goal Evd.sigma -> Goal.goal list Evd.sigma