With gcc 11.3.1, building with -D_FORTIFY_SOURCE=2 shows:
In function ‘getgroups’,
inlined from ‘do_test’ at test-errno.c:129:12:
../misc/sys/cdefs.h:195:6: error: argument 1 value -1 is negative
[-Werror=stringop-overflow=]
195 | ? __ ## f ## _alias (__VA_ARGS__)
\
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../posix/bits/unistd.h:115:10: note: in expansion of macro
‘__glibc_fortify’
115 | return __glibc_fortify (getgroups, __size, sizeof (__gid_t),
| ^~~~~~~~~~~~~~~
../posix/bits/unistd.h: In function ‘do_test’:
../posix/bits/unistd-decl.h:135:28: note: in a call to function
‘__getgroups_alias’ declared with attribute ‘access (write_only, 2, 1)’
135 | extern int __REDIRECT_NTH (__getgroups_alias, (int __size,
__gid_t __list[]),
| ^~~~~~~~~~~~~~~~~
../misc/sys/cdefs.h:264:6: note: in definition of macro ‘__REDIRECT_NTH’
264 | name proto __asm__ (__ASMNAME (#alias)) __THROW
It builds fine with gcc 12 and gcc 13.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
+#include <sys/cdefs.h>
+#include <libc-diag.h>
+#if __GNUC_PREREQ (7, 0)
+/* Triggered by getgroup fortify wrapper. */
+DIAG_IGNORE_NEEDS_COMMENT (7, "-Wstringop-overflow");
+#endif
+
#include <errno.h>
#include <limits.h>
#include <grp.h>
#include <sys/uio.h>
#include <unistd.h>
#include <netinet/in.h>
-#include <libc-diag.h>
/* This is not an exhaustive test: only system calls that can be
persuaded to fail with a consistent error code and no side effects