Re: [PATCH 2/2] selftests/lib.mk: silence some clang warnings that gcc already ignores

From: Shuah Khan
Date: Thu May 30 2024 - 10:26:11 EST


On 5/28/24 20:08, John Hubbard wrote:
gcc defaults to silence (off) for the following warnings, but clang
defaults to the opposite. These warnings are not useful for kselftests,
so silence them for the clang builds as well:

Please you add more information on why they aren't useful
for kselftests.


-Wno-address-of-packed-member
-Wno-gnu-variable-sized-type-not-at-end

This eliminates warnings for the net/ and user_events/ kselftest
subsystems, in these files:

./net/af_unix/scm_rights.c
./net/timestamping.c
./net/ipsec.c
./user_events/perf_test.c

Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
---
tools/testing/selftests/lib.mk | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index 2902787b89b2..41e879f3f8a2 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk
@@ -50,6 +50,12 @@ else
CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%))
endif # CROSS_COMPILE
+# gcc defaults to silence (off) for the following warnings, but clang defaults
+# to the opposite. These warnings are not useful for kselftests, so silence them
+# for the clang builds as well.
+CFLAGS += -Wno-address-of-packed-member
+CFLAGS += -Wno-gnu-variable-sized-type-not-at-end
+
CC := $(CLANG) $(CLANG_FLAGS) -fintegrated-as
else
CC := $(CROSS_COMPILE)gcc

thanks,
-- Shuah