[econstr] Continue consolidation of EConstr API under `interp`.

This commit was motivated by true spurious conversions arising in my
`to_constr` debug branch.

The changes here need careful review as the tradeoffs are subtle and
still a lot of clean up remains to be done in `vernac/*`.

We have opted for penalize [minimally] the few users coming from true
`Constr`-land, but I am sure we can tweak code in a much better way.

In particular, it is not clear if internalization should take an
`evar_map` even in the cases where it is not triggered, see the
changes under `plugins` for a good example.

Also, the new return type of `Pretyping.understand` should undergo
careful review.

We don't touch `Impargs` as it is not clear how to proceed, however,
the current type of `compute_implicits_gen` looks very suspicious as
it is called often with free evars.

Some TODOs are:

- impargs was calling whd_all, the Econstr equivalent can be either
  + Reductionops.whd_all [which does refolding and no sharing]
  + Reductionops.clos_whd_flags with all as a flag.

3 files changed, 8 insertions, 5 deletions

diff --git a/plugins/ssr/ssrcommon.ml b/plugins/ssr/ssrcommon.ml
index 4ae746288..1a02fb91c 100644
--- a/plugins/ssr/ssrcommon.ml
+++ b/plugins/ssr/ssrcommon.ml
@@ -203,7 +203,7 @@ let glob_constr ist genv = function
     let vars = Id.Map.fold (fun x _ accu -> Id.Set.add x accu) ist.Tacinterp.lfun Id.Set.empty in
     let ltacvars = {
       Constrintern.empty_ltac_sign with Constrintern.ltac_vars = vars } in
-    Constrintern.intern_gen Pretyping.WithoutTypeConstraint ~ltacvars genv ce
+    Constrintern.intern_gen Pretyping.WithoutTypeConstraint ~ltacvars genv Evd.(from_env genv) ce
   | rc, None -> rc
 
 let pf_intern_term ist gl (_, c) = glob_constr ist (pf_env gl) c
diff --git a/plugins/ssr/ssrvernac.ml4 b/plugins/ssr/ssrvernac.ml4
index 8e6e0347f..96ded5abf 100644
--- a/plugins/ssr/ssrvernac.ml4
+++ b/plugins/ssr/ssrvernac.ml4
@@ -335,7 +335,8 @@ let push_rels_assum l e =
   push_rels_assum l e
 
 let coerce_search_pattern_to_sort hpat =
-  let env = Global.env () and sigma = Evd.empty in
+  let env = Global.env () in
+  let sigma = Evd.(from_env env) in
   let mkPApp fp n_imps args =
     let args' = Array.append (Array.make n_imps (Pattern.PMeta None)) args in
     Pattern.PApp (fp, args') in
@@ -393,8 +394,9 @@ let interp_search_arg arg =
       interp_search_notation ~loc s key
   | RGlobSearchSubPattern p ->
       try
-        let intern = Constrintern.intern_constr_pattern in 
-        Search.GlobSearchSubPattern (snd (intern (Global.env()) p))
+        let env = Global.env () in
+        let _, p = Constrintern.intern_constr_pattern env (Evd.from_env env) p in
+        Search.GlobSearchSubPattern p
       with e -> let e = CErrors.push e in iraise (ExplainErr.process_vernac_interp_error e)) arg in
   let hpat, a1 = match arg with
   | (_, Search.GlobSearchSubPattern (Pattern.PMeta _)) :: a' -> all_true, a'
diff --git a/plugins/ssr/ssrview.ml b/plugins/ssr/ssrview.ml
index 61b65e347..f2990070b 100644
--- a/plugins/ssr/ssrview.ml
+++ b/plugins/ssr/ssrview.ml
@@ -55,7 +55,8 @@ let in_viewhint =
        Libobject.classify_function = classify_viewhint }
 
 let glob_view_hints lvh =
-  List.map (Constrintern.intern_constr (Global.env ())) lvh
+  let env = Global.env () in
+  List.map (Constrintern.intern_constr env Evd.(from_env env)) lvh
 
 let add_view_hints lvh i = Lib.add_anonymous_leaf (in_viewhint (i, lvh))