On 5/1/24 8:13 AM, Nathan Chancellor wrote:
Hi John,
On Tue, Apr 30, 2024 at 07:08:13PM -0700, John Hubbard wrote:
In order to build with clang at all, in order to see these symptoms, 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
...clang emits a "format string is empty" warning. (gcc also emits a
similar warning.)
The warning you are describing here sounds like the same exact one that
commit caed8eba2215 ("selftests: kselftest_harness: fix Clang warning
about zero-length format") should have addressed in 6.9-rc5. Is this
patch actually necessary?
Apparently not!
Fix by passing NULL, instead of "", for the msg argument to
Because this text is describing what was done in caed8eba2215...
Yes. I took a while between discovering the issue, and posting a fix, I
think that's why.
ksft_test_result_code(). This removes dozens of warnings and a few
errors (some tests have -Werror set).
[1] https://lore.kernel.org/all/20240329-selftests-libmk-llvm-rfc-v1-1-2f9ed7d1c49f@xxxxxxxxxxxxxxx/
Cc: Valentin Obst <kernel@xxxxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Justin Stitt <justinstitt@xxxxxxxxxx>
Cc: Bill Wendling <morbo@xxxxxxxxxx>
Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
---
tools/testing/selftests/kselftest_harness.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/kselftest_harness.h b/tools/testing/selftests/kselftest_harness.h
index d98702b6955d..456b8694e678 100644
--- a/tools/testing/selftests/kselftest_harness.h
+++ b/tools/testing/selftests/kselftest_harness.h
@@ -1207,8 +1207,10 @@ void __run_test(struct __fixture_metadata *f,
else
diagnostic = "unknown";
- ksft_test_result_code(t->exit_code, test_name,
- diagnostic ? "%s" : NULL, diagnostic);
+ if (diagnostic)
+ ksft_test_result_code(t->exit_code, test_name, "%s", diagnostic);
+ else
+ ksft_test_result_code(t->exit_code, test_name, NULL);
but this diff is not doing that because it is based on a tree that has
caed8eba2215; instead, it appears to be a completely identical
transformation?
It's nice to see that someone else had the same fix, anyway. Sorry
about the noise, and yes let's please just drop this one.
thanks,
--
John Hubbard
NVIDIA
