diff options
| author | Willy Tarreau <w@1wt.eu> | 2022-03-23 08:18:06 +0100 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-04-20 17:05:46 -0700 |
| commit | 96980b833a21c6dc29d0dfdc8f211fb8a10256a7 (patch) | |
| tree | 7479441067048a940a0e8d52f97c6b987b9c0198 | |
| parent | 0b37dff10bc05576f9594a10e8ef9c718dab931f (diff) | |
tools/nolibc/string: do not use __builtin_strlen() at -O0
clang wants to use strlen() for __builtin_strlen() at -O0. We don't
really care about -O0 but it at least ought to build, so let's make
sure we don't choke on this, by dropping the optimizationn for
constant strings in this case.
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
| -rw-r--r-- | tools/include/nolibc/string.h | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/tools/include/nolibc/string.h b/tools/include/nolibc/string.h index 0d5e870c7c0b..75a453870498 100644 --- a/tools/include/nolibc/string.h +++ b/tools/include/nolibc/string.h @@ -122,7 +122,9 @@ char *strcpy(char *dst, const char *src) return ret; } -/* this function is only used with arguments that are not constants */ +/* this function is only used with arguments that are not constants or when + * it's not known because optimizations are disabled. + */ static __attribute__((unused)) size_t nolibc_strlen(const char *str) { @@ -132,11 +134,18 @@ size_t nolibc_strlen(const char *str) return len; } +/* do not trust __builtin_constant_p() at -O0, as clang will emit a test and + * the two branches, then will rely on an external definition of strlen(). + */ +#if defined(__OPTIMIZE__) #define strlen(str) ({ \ __builtin_constant_p((str)) ? \ __builtin_strlen((str)) : \ nolibc_strlen((str)); \ }) +#else +#define strlen(str) nolibc_strlen((str)) +#endif static __attribute__((unused)) size_t strlcat(char *dst, const char *src, size_t size) |