diff options
| author | David Laight <David.Laight@ACULAB.COM> | 2023-10-05 11:39:54 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-10-18 14:43:22 -0700 |
| commit | 598f0ac1500d7145c696de4d38797b1dd2c651de (patch) | |
| tree | 54e0103e8eda4c6638b23e77ffd54204a869bd25 /include/linux/compiler.h | |
| parent | fbd126f5a658b92c7f6af986a6d89cf5e5693268 (diff) | |
compiler.h: move __is_constexpr() to compiler.h
Prior to f747e6667ebb2 __is_constexpr() was in its only user minmax.h.
That commit moved it to const.h - but that file just defines ULL(x) and
UL(x) so that constants can be defined for .S and .c files.
So apart from the word 'const' it wasn't really a good location. Instead
move the definition to compiler.h just before the similar
is_signed_type() and is_unsigned_type().
This may not be a good long-term home, but the three definitions belong
together.
Link: https://lkml.kernel.org/r/2a6680bbe2e84459816a113730426782@AcuMS.aculab.com
Signed-off-by: David Laight <david.laight@aculab.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux/compiler.h')
| -rw-r--r-- | include/linux/compiler.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 174099fdc485..bb1339c7057b 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -228,6 +228,14 @@ static inline void *offset_to_ptr(const int *off) #define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) /* + * This returns a constant expression while determining if an argument is + * a constant expression, most importantly without evaluating the argument. + * Glory to Martin Uecker <Martin.Uecker@med.uni-goettingen.de> + */ +#define __is_constexpr(x) \ + (sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8))) + +/* * Whether 'type' is a signed type or an unsigned type. Supports scalar types, * bool and also pointer types. */ |