Sam James <s...@gentoo.org> writes:
> With _FORTIFY_SOURCE >= 2 (enabled by -fhardened), vfprintf-chk-1.c's
> __vfprintf_chk ends up calling __vprintf_chk rather than vprintf.
>
> ```
> --- a/fortify.s
> +++ b/no-fortify.s
> @@ -8,27 +8,28 @@
> [...]
> __vfprintf_chk:
> [...]
> movl $1, should_optimize(%rip)
> - jmp __vfprintf_chk
> + jmp vfprintf@PLT
> ```
Ping.
>
> 2024-02-15 Sam James <s...@gentoo.org>
>
> gcc/testsuite/ChangeLog:
> * gcc.c-torture/execute/vfprintf-chk-1.c (__vfprintf_chk): Undefine
> _FORTIFY_SOURCE
> to call the real vfprintf.
> ---
> The test, AIUI, is trying to test GCC's own basic _chk bits rather than
> any of e.g. glibc's _FORTIFY_SOURCE handling.
>
> I'm curious as to why only vfprintf triggers this right now. If this patch is
> right,
> perhaps we should do printf-chk-1.c, fprintf-chk-1.c, and vprintf-chk-1.
>
> Please push if OK as I don't have access.
>
> gcc/testsuite/gcc.c-torture/execute/vfprintf-chk-1.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/gcc/testsuite/gcc.c-torture/execute/vfprintf-chk-1.c
> b/gcc/testsuite/gcc.c-torture/execute/vfprintf-chk-1.c
> index 401eaf4304a4..a8e5689e3fe6 100644
> --- a/gcc/testsuite/gcc.c-torture/execute/vfprintf-chk-1.c
> +++ b/gcc/testsuite/gcc.c-torture/execute/vfprintf-chk-1.c
> @@ -1,6 +1,7 @@
> /* { dg-skip-if "requires io" { freestanding } } */
>
> #ifndef test
> +#undef _FORTIFY_SOURCE
> #include <stdio.h>
> #include <stdlib.h>
> #include <stdarg.h>
