[gcc/devel/rust/master] gccrs: Take advantage of our new unify_and to inject inference

[Thomas Schwinge]

https://gcc.gnu.org/g:6540653bc29778a5473746bc7463c75204e07c23

commit 6540653bc29778a5473746bc7463c75204e07c23
Author: Philip Herron <herron.philip@googlemail.com>
Date:   Fri Mar 3 18:42:21 2023 +0000

    gccrs: Take advantage of our new unify_and to inject inference
    
    Wen computing higher ranked trait bounds where there are multiple type
    params and ones which are not bound entirely on the impl-type we need
    to inject inference variables as required to compute the types. The
    inference variables we inject are missing the callbacks that we can compute
    the bounds properly so this is the first part of the fix.
    
    Addresses #1893
    
    Signed-off-by: Philip Herron <herron.philip@googlemail.com>
    
    gcc/rust/ChangeLog:
    
            * typecheck/rust-hir-trait-resolve.cc: use unify_and infer

Diff:
---
 gcc/rust/typecheck/rust-hir-trait-resolve.cc | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/gcc/rust/typecheck/rust-hir-trait-resolve.cc b/gcc/rust/typecheck/rust-hir-trait-resolve.cc
index 5a4d9660219..632a60a5366 100644
--- a/gcc/rust/typecheck/rust-hir-trait-resolve.cc
+++ b/gcc/rust/typecheck/rust-hir-trait-resolve.cc
@@ -497,10 +497,12 @@ AssociatedImplTrait::setup_associated_types (
   // the type correctly as our receiver may be generic and we are inferring its
   // generic arguments and this Self might be the concrete version or vice
   // versa.
-  auto result = unify_site (get_impl_block ()->get_mappings ().get_hirid (),
-			    TyTy::TyWithLocation (receiver),
-			    TyTy::TyWithLocation (impl_self_infer),
-			    impl_predicate.get_locus ());
+  auto result = unify_site_and (get_impl_block ()->get_mappings ().get_hirid (),
+				TyTy::TyWithLocation (receiver),
+				TyTy::TyWithLocation (impl_self_infer),
+				impl_predicate.get_locus (),
+				true /*emit-errors*/, true /*commit-if-ok*/,
+				true /*infer*/, true /*cleanup-on-fail*/);
   rust_assert (result->get_kind () != TyTy::TypeKind::ERROR);
   TyTy::BaseType *self_result = result;
 
@@ -525,8 +527,10 @@ AssociatedImplTrait::setup_associated_types (
       TyTy::BaseType *b = hrtb_bound_arguments.at (i);
 
       result
-	= unify_site (a->get_ref (), TyTy::TyWithLocation (a),
-		      TyTy::TyWithLocation (b), impl_predicate.get_locus ());
+	= unify_site_and (a->get_ref (), TyTy::TyWithLocation (a),
+			  TyTy::TyWithLocation (b), impl_predicate.get_locus (),
+			  true /*emit-errors*/, true /*commit-if-ok*/,
+			  true /*infer*/, true /*cleanup-on-fail*/);
       rust_assert (result->get_kind () != TyTy::TypeKind::ERROR);
     }