gccrs: get rid of can_eq in CoerceionRules selection

The can_eq interface is very inconsistent so this begins the journey to
remove this and also address part of #1981

gcc/rust/ChangeLog:

	* typecheck/rust-coercion.cc (TypeCoercionRules::select): use new unify_and interface
	* typecheck/rust-hir-dot-operator.cc (MethodResolver::try_hook): grab bounds behind refs

Signed-off-by: Philip Herron <herron.philip@googlemail.com>

diff --git a/gcc/rust/typecheck/rust-coercion.cc b/gcc/rust/typecheck/rust-coercion.cc
index 74b3882f2c0b3f9cfbfda95cc41d3e094a906b0f..b5d6cef2f79d2cf495325235100158b05e955813 100644 (file)
--- a/gcc/rust/typecheck/rust-coercion.cc
+++ b/gcc/rust/typecheck/rust-coercion.cc
@@ -16,7 +16,6 @@
 // along with GCC; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
-#include "rust-hir-type-check-base.h"
 #include "rust-coercion.h"
 #include "rust-type-util.h"
 
@@ -417,12 +416,18 @@ TypeCoercionRules::select (TyTy::BaseType &autoderefed)
   rust_debug (
     "autoderef type-coercion select autoderefed={%s} can_eq expected={%s}",
     autoderefed.debug_str ().c_str (), expected->debug_str ().c_str ());
-  if (expected->can_eq (&autoderefed, false))
-    {
-      try_result = CoercionResult{adjustments, autoderefed.clone ()};
-      return true;
-    }
-  return false;
+
+  TyTy::BaseType *result
+    = unify_site_and (autoderefed.get_ref (), TyTy::TyWithLocation (expected),
+                     TyTy::TyWithLocation (&autoderefed),
+                     Location () /* locus */, false /*emit_errors*/,
+                     false /*commit_if_ok*/, true /*infer*/, true /*cleanup*/);
+  bool ok = result->get_kind () != TyTy::TypeKind::ERROR;
+  if (!ok)
+    return false;
+
+  try_result = CoercionResult{adjustments, autoderefed.clone ()};
+  return true;
 }
 
 /// Coercing a mutable reference to an immutable works, while

diff --git a/gcc/rust/typecheck/rust-hir-dot-operator.cc b/gcc/rust/typecheck/rust-hir-dot-operator.cc
index 67ff4ad43c640444290b9fc2ef4de063c7540e3d..9f46d13763edb5de6a7def19f39e7ee4972cd59d 100644 (file)
--- a/gcc/rust/typecheck/rust-hir-dot-operator.cc
+++ b/gcc/rust/typecheck/rust-hir-dot-operator.cc
@@ -44,8 +44,23 @@ MethodResolver::Probe (TyTy::BaseType *receiver,
 void
 MethodResolver::try_hook (const TyTy::BaseType &r)
 {
+  rust_debug ("MethodResolver::try_hook get_predicate_items: [%s]",
+             r.debug_str ().c_str ());
   const auto &specified_bounds = r.get_specified_bounds ();
   predicate_items = get_predicate_items (segment_name, r, specified_bounds);
+
+  if (predicate_items.size () > 0)
+    return;
+
+  if (r.get_kind () == TyTy::TypeKind::REF)
+    {
+      const auto &ref = static_cast<const TyTy::ReferenceType &> (r);
+      const auto &element = ref.get_var_element_type ();
+      const auto &element_ty = *element.get_tyty ();
+      const auto &specified_bounds = element_ty.get_specified_bounds ();
+      predicate_items
+       = get_predicate_items (segment_name, element_ty, specified_bounds);
+    }
 }
 
 bool