diff options
| author | John Baldwin <jhb@FreeBSD.org> | 2023-01-27 03:28:22 +0300 |
|---|---|---|
| committer | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2023-08-07 14:45:03 +0300 |
| commit | b12934540f17ba7c22923940e48bfbf02d0ae082 (patch) | |
| tree | 09c4969e36dcfc23caee6ce20ca220f45bab8fc7 /newlib/libc | |
| parent | 3b4f6217c371cf70d5ec5137436cfa5892bb45e8 (diff) | |
<sys/cdefs.h>: Decay expression passed to fallback
version of __generic()
This ensures that __generic() more closely matches _Generic() when
using the fallback version when _Generic() is not available (such as
GCC).
Co-authored by: jrtc27
Reviewed by: jrtc27
Differential Revision: https://reviews.freebsd.org/D38215
Diffstat (limited to 'newlib/libc')
| -rw-r--r-- | newlib/libc/include/sys/cdefs.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/newlib/libc/include/sys/cdefs.h b/newlib/libc/include/sys/cdefs.h index 720e70092..808498c50 100644 --- a/newlib/libc/include/sys/cdefs.h +++ b/newlib/libc/include/sys/cdefs.h @@ -328,6 +328,9 @@ * __generic(). Unlike _Generic(), this macro can only distinguish * between a single type, so it requires nested invocations to * distinguish multiple cases. + * + * Note that the comma operator is used to force expr to decay in + * order to match _Generic(). */ #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \ @@ -337,7 +340,7 @@ #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus) #define __generic(expr, t, yes, no) \ __builtin_choose_expr( \ - __builtin_types_compatible_p(__typeof(expr), t), yes, no) + __builtin_types_compatible_p(__typeof((0, (expr))), t), yes, no) #endif /* |