diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 777f08a2edbedd3779f5287b8a4b80777caf28b3..a7595478ecb2fddd4100ff7f5fbaa90b26475141 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2010-05-06  Jason Merrill  <jason@redhat.com>
+
+	* gimplify.c (gimplify_modify_expr_rhs): Don't return GS_OK for
+	stripping WITH_SIZE_EXPR.
+	(gimplify_expr) [MODIFY_EXPR]: Trust GS_OK even if the rhs didn't
+	change.
+
 2010-05-06  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* config.gcc: Removed mips-sgi-irix5*, mips-sgi-irix6.[0-4]* from
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index 8d2bc582a7a8fae29e55eacbdc636f70aae5b01c..51ec4b5633d2e5ba6eeb66c4016dcc40dc6556c4 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -4291,7 +4291,10 @@ gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p,
 	  if (TREE_CODE (TREE_OPERAND (*from_p, 0)) == CALL_EXPR)
 	    {
 	      *from_p = TREE_OPERAND (*from_p, 0);
-	      ret = GS_OK;
+	      /* We don't change ret in this case because the
+		 WITH_SIZE_EXPR might have been added in
+		 gimplify_modify_expr, so returning GS_OK would lead to an
+		 infinite loop.  */
 	      changed = true;
 	    }
 	  break;
@@ -6628,16 +6631,12 @@ gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
 
 	case MODIFY_EXPR:
 	case INIT_EXPR:
-	  {
-	    tree from = TREE_OPERAND (*expr_p, 1);
-	    ret = gimplify_modify_expr (expr_p, pre_p, post_p,
-					fallback != fb_none);
-	    /* Don't let the end of loop logic change GS_OK into GS_ALL_DONE
-	       if the RHS has changed.  */
-	    if (ret == GS_OK && *expr_p == save_expr
-		&& TREE_OPERAND (*expr_p, 1) != from)
-	      continue;
-	  }
+	  ret = gimplify_modify_expr (expr_p, pre_p, post_p,
+				      fallback != fb_none);
+	  /* Don't let the end of loop logic change GS_OK to GS_ALL_DONE;
+	     gimplify_modify_expr_rhs might have changed the RHS.  */
+	  if (ret == GS_OK && *expr_p)
+	    continue;
 	  break;
 
 	case TRUTH_ANDIF_EXPR: