gcc/gcc43-pr37103.patch
Jakub Jelinek f60b61efff 4.3.1-7
2008-08-14 07:10:39 +00:00

57 lines
1.5 KiB
Diff

2008-08-13 Jakub Jelinek <jakub@redhat.com>
PR middle-end/37103
* fold-const.c (fold_widened_comparison): Do not allow
sign changes that change the result even if shorter type
is wider than arg1_unw's type.
* gcc.c-torture/execute/20080813-1.c: New test.
--- gcc/fold-const.c.jj 2008-08-13 19:46:11.000000000 +0200
+++ gcc/fold-const.c 2008-08-13 20:18:21.000000000 +0200
@@ -6733,10 +6733,8 @@ fold_widened_comparison (enum tree_code
if ((code == EQ_EXPR || code == NE_EXPR
|| TYPE_UNSIGNED (TREE_TYPE (arg0)) == TYPE_UNSIGNED (shorter_type))
&& (TREE_TYPE (arg1_unw) == shorter_type
- || (TYPE_PRECISION (shorter_type)
- > TYPE_PRECISION (TREE_TYPE (arg1_unw)))
|| ((TYPE_PRECISION (shorter_type)
- == TYPE_PRECISION (TREE_TYPE (arg1_unw)))
+ >= TYPE_PRECISION (TREE_TYPE (arg1_unw)))
&& (TYPE_UNSIGNED (shorter_type)
== TYPE_UNSIGNED (TREE_TYPE (arg1_unw))))
|| (TREE_CODE (arg1_unw) == INTEGER_CST
--- gcc/testsuite/gcc.c-torture/execute/20080813-1.c.jj 2008-08-13 20:22:56.000000000 +0200
+++ gcc/testsuite/gcc.c-torture/execute/20080813-1.c 2008-08-13 20:22:10.000000000 +0200
@@ -0,0 +1,30 @@
+/* PR middle-end/37103 */
+
+extern void abort (void);
+
+void
+foo (unsigned short x)
+{
+ signed char y = -1;
+ if (x == y)
+ abort ();
+}
+
+void
+bar (unsigned short x)
+{
+ unsigned char y = -1;
+ if (x == y)
+ abort ();
+}
+
+int
+main (void)
+{
+ if (sizeof (int) == sizeof (short))
+ return 0;
+ foo (-1);
+ if (sizeof (short) > 1)
+ bar (-1);
+ return 0;
+}