diff options
Diffstat (limited to 'pretyping/unification.ml')
| -rw-r--r-- | pretyping/unification.ml | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/pretyping/unification.ml b/pretyping/unification.ml index 203b1ec8..01e1154e 100644 --- a/pretyping/unification.ml +++ b/pretyping/unification.ml @@ -673,6 +673,10 @@ let rec unify_0_with_initial_metas (sigma,ms,es as subst) conv_at_top env cv_pb (sigma,(k,lift (-nb) cM,fst (extract_instance_status pb))::metasubst, evarsubst) else error_cannot_unify_local curenv sigma (m,n,cM) + | Evar (evk,_ as ev), Evar (evk',_) + when not (Evar.Set.mem evk flags.frozen_evars) + && Evar.equal evk evk' -> + sigma,metasubst,((curenv,ev,cN)::evarsubst) | Evar (evk,_ as ev), _ when not (Evar.Set.mem evk flags.frozen_evars) && not (occur_evar evk cN) -> @@ -1673,11 +1677,13 @@ let w_unify_to_subterm env evd ?(flags=default_unify_flags ()) (op,cl) = matchrec t with ex when precatchable_exception ex -> matchrec c) + | Lambda (_,t,c) -> (try matchrec t with ex when precatchable_exception ex -> matchrec c) + | _ -> error "Match_subterm")) in try matchrec cl @@ -1774,7 +1780,12 @@ let w_unify_to_subterm_list env evd flags hdmeta oplist t = try (* This is up to delta for subterms w/o metas ... *) w_unify_to_subterm env evd ~flags (strip_outer_cast op,t) - with PretypeError (env,_,NoOccurrenceFound _) when allow_K -> (evd,op) + with PretypeError (env,_,NoOccurrenceFound _) when + allow_K || + (* w_unify_to_subterm does not go through evars, so + the next step, which was already in <= 8.4, is + needed at least for compatibility of rewrite *) + dependent op t -> (evd,op) in if not allow_K && (* ensure we found a different instance *) |