tst-setcontext10.c: Undef _FORTIFY_SOURCE

When _FORTIFY_SOURCE is defined to 2, ____longjmp_chk is called,
instead of longjmp.  ____longjmp_chk compares the relative stack
values to decide if it is called from a stack frame which called
setjmp.  If not, ____longjmp_chk assumes that an alternate signal
stack is used.  Since comparing the relative stack values isn't
reliable with user context, when there is no signal, ____longjmp_chk
will fail.  Undefine _FORTIFY_SOURCE to avoid ____longjmp_chk in
user context test.
This commit is contained in:
H.J. Lu 2023-12-19 09:55:25 -08:00
parent cad5703e4f
commit 46432be2f1

View File

@ -16,6 +16,15 @@
License along with the GNU C Library; if not, see License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */ <https://www.gnu.org/licenses/>. */
/* When _FORTIFY_SOURCE is defined to 2, ____longjmp_chk is called,
instead of longjmp. ____longjmp_chk compares the relative stack
values to decide if it is called from a stack frame which called
setjmp. If not, ____longjmp_chk assumes that an alternate signal
stack is used. Since comparing the relative stack values isn't
reliable with user context, when there is no signal, ____longjmp_chk
will fail. Undefine _FORTIFY_SOURCE to avoid ____longjmp_chk. */
#undef _FORTIFY_SOURCE
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <setjmp.h> #include <setjmp.h>