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Hi!
When glibc is built with gcc-4_0-branch on IA-64, tst-getpid{1,2}
fails. The problem is that while older GCCs always aligned
buffer as big as char st[256 * 1024]; to 16 bytes, GCC 4 only
aligns this to 8 bytes.
Now, either we require direct clone/__clone2 users to make sure
the stack passed to it is sufficiently aligned (as done e.g. in
the patch below, 64 is just a guess for all arches out there,
I think e.g. IA-64 needs just 16 bytes alingment), or we make sure
that glibc's __clone2 and clone align things themselves, or we
make sure the kernel aligns it.
2005-03-08 Jakub Jelinek <jakub@redhat.com>
* tst-getpid1.c: Include stdint.h.
(do_test): Align stack passed to clone{2,} to 64 bytes.
--- libc/nptl/tst-getpid1.c.jj 2004-12-15 12:16:06.000000000 +0100
+++ libc/nptl/tst-getpid1.c 2005-03-08 16:54:43.947924210 +0100
@@ -1,6 +1,7 @@
#include <sched.h>
#include <signal.h>
#include <string.h>
+#include <stdint.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
@@ -44,11 +45,13 @@ do_test (void)
extern int __clone2 (int (*__fn) (void *__arg), void *__child_stack_base,
size_t __child_stack_size, int __flags,
void *__arg, ...);
- char st[256 * 1024];
- pid_t p = __clone2 (f, st, sizeof (st), TEST_CLONE_FLAGS, 0);
+ char st[256 * 1024 + 64];
+ char *stp = (char *) ((uintptr_t) (st + 64) & -64);
+ pid_t p = __clone2 (f, stp, sizeof (st) - 64, TEST_CLONE_FLAGS, 0);
#else
- char st[128 * 1024];
- pid_t p = clone (f, st + sizeof (st), TEST_CLONE_FLAGS, 0);
+ char st[128 * 1024 + 64];
+ char *stp = (char *) ((uintptr_t) (st + 64) & -64);
+ pid_t p = clone (f, stp + sizeof (st) - 64, TEST_CLONE_FLAGS, 0);
#endif
if (p == -1)
{
Jakub
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