[PATCH v2] selftest/timerns: fix clang build failures for abs() calls

[John Hubbard]

First of all, in order to build with clang at all, one must first apply
Valentin Obst's build fix for LLVM [1]. Once that is done, then when
building with clang, via:

    make LLVM=1 -C tools/testing/selftests

..then clang warns about mismatches between the expected and required
integer length being supplied to abs(3).

Fix this by using the correct variant of abs(3): labs(3) or llabs(3), in
these cases.

[1] https://lore.kernel.org/all/20240329-selftests-libmk-llvm-rfc-v1-1-2f9ed7d1c49f@xxxxxxxxxxxxxxx/

Reviewed-by: Dmitry Safonov <dima@xxxxxxxxxx>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
---

Changes since the first version:

1) Rebased onto Linux 6.10-rc1

2) Reviewed-by's added.

thanks,
John Hubbard


 tools/testing/selftests/timens/exec.c       | 6 +++---
 tools/testing/selftests/timens/timer.c      | 2 +-
 tools/testing/selftests/timens/timerfd.c    | 2 +-
 tools/testing/selftests/timens/vfork_exec.c | 4 ++--
 4 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/timens/exec.c b/tools/testing/selftests/timens/exec.c
index e40dc5be2f66..d12ff955de0d 100644
--- a/tools/testing/selftests/timens/exec.c
+++ b/tools/testing/selftests/timens/exec.c
@@ -30,7 +30,7 @@ int main(int argc, char *argv[])
 
 		for (i = 0; i < 2; i++) {
 			_gettime(CLOCK_MONOTONIC, &tst, i);
-			if (abs(tst.tv_sec - now.tv_sec) > 5)
+			if (labs(tst.tv_sec - now.tv_sec) > 5)
 				return pr_fail("%ld %ld\n", now.tv_sec, tst.tv_sec);
 		}
 		return 0;
@@ -50,7 +50,7 @@ int main(int argc, char *argv[])
 
 	for (i = 0; i < 2; i++) {
 		_gettime(CLOCK_MONOTONIC, &tst, i);
-		if (abs(tst.tv_sec - now.tv_sec) > 5)
+		if (labs(tst.tv_sec - now.tv_sec) > 5)
 			return pr_fail("%ld %ld\n",
 					now.tv_sec, tst.tv_sec);
 	}
@@ -70,7 +70,7 @@ int main(int argc, char *argv[])
 		/* Check that a child process is in the new timens. */
 		for (i = 0; i < 2; i++) {
 			_gettime(CLOCK_MONOTONIC, &tst, i);
-			if (abs(tst.tv_sec - now.tv_sec - OFFSET) > 5)
+			if (labs(tst.tv_sec - now.tv_sec - OFFSET) > 5)
 				return pr_fail("%ld %ld\n",
 						now.tv_sec + OFFSET, tst.tv_sec);
 		}
diff --git a/tools/testing/selftests/timens/timer.c b/tools/testing/selftests/timens/timer.c
index 5e7f0051bd7b..5b939f59dfa4 100644
--- a/tools/testing/selftests/timens/timer.c
+++ b/tools/testing/selftests/timens/timer.c
@@ -56,7 +56,7 @@ int run_test(int clockid, struct timespec now)
 			return pr_perror("timerfd_gettime");
 
 		elapsed = new_value.it_value.tv_sec;
-		if (abs(elapsed - 3600) > 60) {
+		if (llabs(elapsed - 3600) > 60) {
 			ksft_test_result_fail("clockid: %d elapsed: %lld\n",
 					      clockid, elapsed);
 			return 1;
diff --git a/tools/testing/selftests/timens/timerfd.c b/tools/testing/selftests/timens/timerfd.c
index 9edd43d6b2c1..a4196bbd6e33 100644
--- a/tools/testing/selftests/timens/timerfd.c
+++ b/tools/testing/selftests/timens/timerfd.c
@@ -61,7 +61,7 @@ int run_test(int clockid, struct timespec now)
 			return pr_perror("timerfd_gettime(%d)", clockid);
 
 		elapsed = new_value.it_value.tv_sec;
-		if (abs(elapsed - 3600) > 60) {
+		if (llabs(elapsed - 3600) > 60) {
 			ksft_test_result_fail("clockid: %d elapsed: %lld\n",
 					      clockid, elapsed);
 			return 1;
diff --git a/tools/testing/selftests/timens/vfork_exec.c b/tools/testing/selftests/timens/vfork_exec.c
index beb7614941fb..5b8907bf451d 100644
--- a/tools/testing/selftests/timens/vfork_exec.c
+++ b/tools/testing/selftests/timens/vfork_exec.c
@@ -32,7 +32,7 @@ static void *tcheck(void *_args)
 
 	for (i = 0; i < 2; i++) {
 		_gettime(CLOCK_MONOTONIC, &tst, i);
-		if (abs(tst.tv_sec - now->tv_sec) > 5) {
+		if (labs(tst.tv_sec - now->tv_sec) > 5) {
 			pr_fail("%s: in-thread: unexpected value: %ld (%ld)\n",
 				args->tst_name, tst.tv_sec, now->tv_sec);
 			return (void *)1UL;
@@ -64,7 +64,7 @@ static int check(char *tst_name, struct timespec *now)
 
 	for (i = 0; i < 2; i++) {
 		_gettime(CLOCK_MONOTONIC, &tst, i);
-		if (abs(tst.tv_sec - now->tv_sec) > 5)
+		if (labs(tst.tv_sec - now->tv_sec) > 5)
 			return pr_fail("%s: unexpected value: %ld (%ld)\n",
 					tst_name, tst.tv_sec, now->tv_sec);
 	}

base-commit: 2bfcfd584ff5ccc8bb7acde19b42570414bf880b
-- 
2.45.1