diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-11 08:40:01 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-11 08:40:01 -0700 |
commit | 21f9c8a13bb2a0c24d9c6b86bc0896542a28c197 (patch) | |
tree | 9a7d1edcec7bb8a02dace5115bd35fa9d63204fd | |
parent | ffcf9c5700e49c0aee42dcba9a12ba21338e8136 (diff) |
Revert "Makefile.extrawarn: re-enable -Wformat for clang"
This reverts commit 258fafcd0683d9ccfa524129d489948ab3ddc24c.
The clang -Wformat warning is terminally broken, and the clang people
can't seem to get their act together.
This test program causes a warning with clang:
#include <stdio.h>
int main(int argc, char **argv)
{
printf("%hhu\n", 'a');
}
resulting in
t.c:5:19: warning: format specifies type 'unsigned char' but the argument has type 'int' [-Wformat]
printf("%hhu\n", 'a');
~~~~ ^~~
%d
and apparently clang people consider that a feature, because they don't
want to face the reality of how either C character constants, C
arithmetic, and C varargs functions work.
The rest of the world just shakes their head at that kind of
incompetence, and turns off -Wformat for clang again.
And no, the "you should use a pointless cast to shut this up" is not a
valid answer. That warning should not exist in the first place, or at
least be optinal with some "-Wformat-me-harder" kind of option.
[ Admittedly, there's also very little reason to *ever* use '%hh[ud]' in
C, but what little reason there is is entirely about 'I want to see
only the low 8 bits of the argument'. So I would suggest nobody ever
use that format in the first place, but if they do, the clang
behavious is simply always wrong. Because '%hhu' takes an 'int'. It's
that simple. ]
Reported-by: Sudip Mukherjee (Codethink) <sudipm.mukherjee@gmail.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | scripts/Makefile.extrawarn | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index 9bbaf7112a9b..f5f0d6f09053 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -47,6 +47,7 @@ else ifdef CONFIG_CC_IS_CLANG KBUILD_CFLAGS += -Wno-initializer-overrides +KBUILD_CFLAGS += -Wno-format KBUILD_CFLAGS += -Wno-sign-compare KBUILD_CFLAGS += -Wno-format-zero-length KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast) |