diff options
Diffstat (limited to 'lib/stddef.in.h')
-rw-r--r-- | lib/stddef.in.h | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/lib/stddef.in.h b/lib/stddef.in.h index e146063c026..2e50a1f01e8 100644 --- a/lib/stddef.in.h +++ b/lib/stddef.in.h @@ -83,20 +83,26 @@ /* Some platforms lack max_align_t. The check for _GCC_MAX_ALIGN_T is a hack in case the configure-time test was done with g++ even though - we are currently compiling with gcc. */ -#if ! (@HAVE_MAX_ALIGN_T@ || defined _GCC_MAX_ALIGN_T) -# if !GNULIB_defined_max_align_t + we are currently compiling with gcc. + On MSVC, max_align_t is defined only in C++ mode, after <cstddef> was + included. Its definition is good since it has an alignment of 8 (on x86 + and x86_64). */ +#if defined _MSC_VER && defined __cplusplus +# include <cstddef> +#else +# if ! (@HAVE_MAX_ALIGN_T@ || defined _GCC_MAX_ALIGN_T) +# if !GNULIB_defined_max_align_t /* On the x86, the maximum storage alignment of double, long, etc. is 4, but GCC's C11 ABI for x86 says that max_align_t has an alignment of 8, and the C11 standard allows this. Work around this problem by using __alignof__ (which returns 8 for double) rather than _Alignof (which returns 4), and align each union member accordingly. */ -# ifdef __GNUC__ -# define _GL_STDDEF_ALIGNAS(type) \ - __attribute__ ((__aligned__ (__alignof__ (type)))) -# else -# define _GL_STDDEF_ALIGNAS(type) /* */ -# endif +# ifdef __GNUC__ +# define _GL_STDDEF_ALIGNAS(type) \ + __attribute__ ((__aligned__ (__alignof__ (type)))) +# else +# define _GL_STDDEF_ALIGNAS(type) /* */ +# endif typedef union { char *__p _GL_STDDEF_ALIGNAS (char *); @@ -104,8 +110,9 @@ typedef union long double __ld _GL_STDDEF_ALIGNAS (long double); long int __i _GL_STDDEF_ALIGNAS (long int); } rpl_max_align_t; -# define max_align_t rpl_max_align_t -# define GNULIB_defined_max_align_t 1 +# define max_align_t rpl_max_align_t +# define GNULIB_defined_max_align_t 1 +# endif # endif #endif |