ulonglong.m4

来自「linux平台中」· M4 代码 · 共 18 行

#serial 2

dnl From Paul Eggert.

AC_DEFUN(jm_AC_TYPE_UNSIGNED_LONG_LONG,
[
  AC_CACHE_CHECK([for unsigned long long], ac_cv_type_unsigned_long_long,
  [AC_TRY_LINK([unsigned long long ull = 1; int i = 63;],
    [unsigned long long ullmax = (unsigned long long) -1;
     return ull << i | ull >> i | ullmax / ull | ullmax % ull;],
    ac_cv_type_unsigned_long_long=yes,
    ac_cv_type_unsigned_long_long=no)])
  if test $ac_cv_type_unsigned_long_long = yes; then
    AC_DEFINE(HAVE_UNSIGNED_LONG_LONG, 1,
      [Define if you have the unsigned long long type.])
  fi
])