On 2020-02-11, shuah shuah@kernel.org wrote:

openat2:

tools/testing/selftests/openat2' gcc -Wall -O2 -g -fsanitize=address -fsanitize=undefined openat2_test.c helpers.c -o tools/testing/selftests/openat2/openat2_test In file included from /usr/include/fcntl.h:301, from helpers.c:9: In function ‘openat’, inlined from ‘touchat’ at helpers.c:49:11: /usr/include/x86_64-linux-gnu/bits/fcntl2.h:126:4: error: call to ‘__openat_missing_mode’ declared with attribute error: openat with O_CREAT or O_TMPFILE in third argument needs 4 arguments 126 | __openat_missing_mode (); | ^~~~~~~~~~~~~~~~~~~~~~~~

Yeah, that's a brain-o -- it looks like you have a newer glibc than me which gives you a warning when you don't set the mode. The fix should be just the following:

--8<----------------------------------------------------------------------- Subject: [PATCH] selftests: openat2: fix build error on newer glibc

It appears that newer glibcs check that openat(O_CREAT) was provided a fourth argument (rather than passing garbage), resulting in the following build error:

In file included from /usr/include/fcntl.h:301, from helpers.c:9: In function ‘openat’, inlined from ‘touchat’ at helpers.c:49:11: /usr/include/x86_64-linux-gnu/bits/fcntl2.h:126:4: error: call to ‘__openat_missing_mode’ declared with attribute error: openat with O_CREAT or O_TMPFILE in third argument needs 4 arguments 126 | __openat_missing_mode (); | ^~~~~~~~~~~~~~~~~~~~~~~~

Reported-by: Shuah Khan shuah@kernel.org Signed-off-by: Aleksa Sarai cyphar@cyphar.com --- tools/testing/selftests/openat2/helpers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/openat2/helpers.c b/tools/testing/selftests/openat2/helpers.c index e9a6557ab16f..5074681ffdc9 100644 --- a/tools/testing/selftests/openat2/helpers.c +++ b/tools/testing/selftests/openat2/helpers.c @@ -46,7 +46,7 @@ int sys_renameat2(int olddirfd, const char *oldpath,

int touchat(int dfd, const char *path) { - int fd = openat(dfd, path, O_CREAT); + int fd = openat(dfd, path, O_CREAT, 0700); if (fd >= 0) close(fd); return fd;