* tree.c (unsave_expr_now): Handle NULL_TREE as input.

From-SVN: r30665

gcc/ChangeLog

+1999-11-25  Mark Mitchell  <mark@codesourcery.com>
+
+	* tree.c (unsave_expr_now): Handle NULL_TREE as input.
+
 Wed Nov 24 17:08:09 MET 1999  Jan Hubicka  <hubicka@freesoft.cz>
 
 	* reg-stack.c (subst_stack_regs_pat): Swap operands in commutative

gcc/tree.c

@@ -2469,6 +2469,10 @@ unsave_expr_now_r (expr)
 {
   enum tree_code code;
 
+  /* There's nothing to do for NULL_TREE.  */
+  if (!expr)
+    return;
+
   unsave_expr_1 (expr);
 
   code = TREE_CODE (expr);