wordsize.h

来自「glibc 库, 不仅可以学习使用库函数,还可以学习函数的具体实现,是提高功力的」· C头文件 代码 · 共 21 行

/* Determine the wordsize from the preprocessor defines.  */

#if defined __arch64__ || defined __sparcv9
# define __WORDSIZE	64
#else
# define __WORDSIZE	32
#endif

#if !defined __NO_LONG_DOUBLE_MATH && !defined __LONG_DOUBLE_MATH_OPTIONAL

# if __WORDSIZE == 32
/* Signal that in 32bit ABI we didn't used to have a `long double'.
   The changes all the `long double' function variants to be redirects
   to the double functions.  */
#  define __LONG_DOUBLE_MATH_OPTIONAL   1
#  ifndef __LONG_DOUBLE_128__
#   define __NO_LONG_DOUBLE_MATH        1
#  endif
# endif
#endif