convert.c (convert_to_integer): Don't do unsigned unless result or both inputs are unsigned.

	* convert.c (convert_to_integer): Don't do unsigned unless result or
	both inputs are unsigned.

From-SVN: r40014

gcc/ChangeLog

 Fri Feb 23 15:28:39 2001  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
 
+	* convert.c (convert_to_integer): Don't do unsigned unless result or
+	both inputs are unsigned.
+
 	* fold-const.c (fold_convert): Don't call size_int_type_wide if
 	input overflows.
 

gcc/convert.c

@@ -310,13 +310,13 @@ convert_to_integer (type, expr)
 		  {
 		    /* Don't do unsigned arithmetic where signed was wanted,
 		       or vice versa.
-		       Exception: if either of the original operands were
+		       Exception: if both of the original operands were
 		       unsigned then can safely do the work as unsigned.
 		       And we may need to do it as unsigned
 		       if we truncate to the original size.  */
 		    typex = ((TREE_UNSIGNED (TREE_TYPE (expr))
-			      || TREE_UNSIGNED (TREE_TYPE (arg0))
-			      || TREE_UNSIGNED (TREE_TYPE (arg1)))
+			      || (TREE_UNSIGNED (TREE_TYPE (arg0))
+				  && TREE_UNSIGNED (TREE_TYPE (arg1))))
 			     ? unsigned_type (typex) : signed_type (typex));
 		    return convert (type,
 				    fold (build (ex_form, typex,