tree-nested.c (convert_local_reference): Handle VIEW_CONVERT_EXPR.

	* tree-nested.c (convert_local_reference): Handle VIEW_CONVERT_EXPR.
	Request walking the subtrees only, leaving the current is_lhs/val_only
	untouched.
	(convert_non_local_reference): Likewise.

	testsuite/
	* gnat.dg/lhs_view_convert.adb: New test.

From-SVN: r125646

gcc/ChangeLog

+2007-06-12  Olivier Hainque  <hainque@adacore.com>
+
+	* tree-nested.c (convert_local_reference): Handle VIEW_CONVERT_EXPR.
+	Request walking the subtrees only, leaving the current is_lhs/val_only
+	untouched.
+	(convert_non_local_reference): Likewise.
+	
 2007-06-12  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* config/m68k/m68k-devices.def (52221, 52223, 5253): New.

gcc/testsuite/ChangeLog

+2007-06-12  Olivier Hainque  <hainque@adacore.com>
+
+	* gnat.dg/lhs_view_convert.adb: New test.
+
 2007-06-12  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/15353

gcc/testsuite/gnat.dg/lhs_view_convert.adb

+-- { dg-do run }
+-- { dg-options "-gnatp" }
+
+procedure Lhs_View_Convert is
+
+   type Root is tagged record
+      RV : Natural;
+   end record;
+
+   type Derived is new Root with null record;
+
+   Root_Instance : Root := (RV => 1);
+
+   Derived_Instance : Derived;
+
+   procedure Process is
+      X : Natural := Derived_Instance.RV;
+   begin
+      null;
+   end;
+begin
+   Derived_Instance.RV := 2;
+   
+   Root (Derived_Instance) := Root (Root_Instance);
+   
+   if Derived_Instance.RV /= Root_Instance.RV then
+      raise Program_Error;
+   end if;
+end;

gcc/tree-nested.c

@@ -1035,6 +1035,13 @@ convert_nonlocal_reference (tree *tp, int *walk_subtrees, void *data)
       walk_tree (tp, convert_nonlocal_reference, wi, NULL);
       break;
 
+    case VIEW_CONVERT_EXPR:
+      /* Just request to look at the subtrees, leaving val_only and lhs
+	 untouched.  This might actually be for !val_only + lhs, in which
+	 case we don't want to force a replacement by a temporary.  */
+      *walk_subtrees = 1;
+      break;
+
     case OMP_PARALLEL:
       save_suppress = info->suppress_expansion;
       if (convert_nonlocal_omp_clauses (&OMP_PARALLEL_CLAUSES (t), wi))
@@ -1313,6 +1320,13 @@ convert_local_reference (tree *tp, int *walk_subtrees, void *data)
       wi->val_only = save_val_only;
       break;
 
+    case VIEW_CONVERT_EXPR:
+      /* Just request to look at the subtrees, leaving val_only and lhs
+	 untouched.  This might actually be for !val_only + lhs, in which
+	 case we don't want to force a replacement by a temporary.  */
+      *walk_subtrees = 1;
+      break;
+
     case OMP_PARALLEL:
       save_suppress = info->suppress_expansion;
       if (convert_local_omp_clauses (&OMP_PARALLEL_CLAUSES (t), wi))