------- Comment #7 from sandra at codesourcery dot com 2010-07-07 00:42 -------
Hmmm. It's possible I built my toolchain incorrectly, but I'm seeing that it
aborts when compiled with -m64 but not with -m32. The failure mode looks
identical to that reported in PR39794:
(gdb) print a
$1 = {0, 1, 4, 2, 10, 12, 24, 44, 72, 92, 60, 34, 244, 47, 58, 291}
(gdb) print ref
$2 = {0, 1, 4, 2, 10, 12, 24, 44, 72, 136, 232, 416, 736, 1296, 2304, 2032}
This slightly modified version of the test case fails when compiled with -m64
-O2 -funroll-loops -fno-ivopts:
extern void abort ();
void
foo (int *a, int n)
{
int *lasta = a + n;
for (; a != lasta; a++)
{
*a *= 2;
a[1] = a[-1] + a[-2];
}
}
int a[16];
int ref[16] = { 0, 1, 4, 2, 10, 12, 24, 44,
72, 136, 232, 416, 736, 1296, 2304, 2032 };
int
main ()
{
int i;
for (i = 0; i < 16; i++)
a[i] = i;
foo (a + 2, 16 - 3);
for (i = 0; i < 16; i++)
if (ref[i] != a[i])
abort ();
return 0;
}
So, not an ivopts problem at all?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44838
