(get_narrower): Preserve unsignedness when bitschange == 0.

From-SVN: r4842

diff --git a/gcc/tree.c b/gcc/tree.c
index 82bf4ccc07a223bcc3e79ec574127fcc9caaf0e7..5f57d4347bb1dfe8dd158c29724133d241b86dcf 100644 (file)
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -3162,7 +3162,14 @@ get_narrower (op, unsignedp_ptr)
            break;
          first = 0;
        }
-      /* A change in nominal type can always be stripped.  */
+      else /* bitschange == 0 */
+       {
+         /* A change in nominal type can always be stripped, but we must
+            preserve the unsignedness.  */
+         if (first)
+           uns = TREE_UNSIGNED (TREE_TYPE (op));
+         first = 0;
+       }
 
       win = op;
     }