| From: Justin Stitt <jstitt007@gmail.com> |
| Subject: include/uapi/linux/swab.h: move explicit cast outside ternary |
| Date: Wed, 8 Jun 2022 15:35:39 -0700 |
| |
| A cast inside __builtin_constant_p doesn't do anything since it should |
| evaluate as constant at compile time irrespective of this cast. Instead, |
| I moved this cast outside the ternary to ensure the return type is as |
| expected. |
| |
| Additionally, if __HAVE_BUILTIN_BSWAP16__ was not defined then __swab16 is |
| actually returning an `int` not a `u16` due to integer promotion. |
| |
| As Al Viro notes: |
| You *can't* get smaller-than-int out of ? :, same as you can't get it |
| out of addition, etc. |
| |
| This also fixes some clang -Wformat warnings involving default |
| argument promotion. |
| |
| Link: https://github.com/ClangBuiltLinux/linux/issues/378 |
| Link: https://lkml.kernel.org/r/20220608223539.470472-1-justinstitt@google.com |
| Signed-off-by: Justin Stitt <jstitt007@gmail.com> |
| Suggested-by: Al Viro <viro@zeniv.linux.org.uk> |
| Suggested-by: Nathan Chancellor <nathan@kernel.org> |
| Reviewed-by: Nathan Chancellor <nathan@kernel.org> |
| Suggested-by: Nick Desaulniers <ndesaulniers@google.com> |
| Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
| --- |
| |
| include/uapi/linux/swab.h | 6 +++--- |
| 1 file changed, 3 insertions(+), 3 deletions(-) |
| |
| --- a/include/uapi/linux/swab.h~include-uapi-linux-swabh-move-explicit-cast-outside-ternary |
| +++ a/include/uapi/linux/swab.h |
| @@ -102,7 +102,7 @@ static inline __attribute_const__ __u32 |
| #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) |
| #else |
| #define __swab16(x) \ |
| - (__builtin_constant_p((__u16)(x)) ? \ |
| + (__u16)(__builtin_constant_p(x) ? \ |
| ___constant_swab16(x) : \ |
| __fswab16(x)) |
| #endif |
| @@ -115,7 +115,7 @@ static inline __attribute_const__ __u32 |
| #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) |
| #else |
| #define __swab32(x) \ |
| - (__builtin_constant_p((__u32)(x)) ? \ |
| + (__u32)(__builtin_constant_p(x) ? \ |
| ___constant_swab32(x) : \ |
| __fswab32(x)) |
| #endif |
| @@ -128,7 +128,7 @@ static inline __attribute_const__ __u32 |
| #define __swab64(x) (__u64)__builtin_bswap64((__u64)(x)) |
| #else |
| #define __swab64(x) \ |
| - (__builtin_constant_p((__u64)(x)) ? \ |
| + (__u64)(__builtin_constant_p(x) ? \ |
| ___constant_swab64(x) : \ |
| __fswab64(x)) |
| #endif |
| _ |