third_party/tcmalloc/vendor/m4/compiler_characteristics.m4

   1 # Check compiler characteristics (e.g. type sizes, PRIxx macros, ...)
   2
   3 # If types $1 and $2 are compatible, perform action $3
   4 AC_DEFUN([AC_TYPES_COMPATIBLE],
   5   [AC_TRY_COMPILE([#include <stddef.h>], [$1 v1 = 0; $2 v2 = 0; return (&v1 - &v2)], $3)])
   6
   7 define(AC_PRIUS_COMMENT, [printf format code for printing a size_t and ssize_t])
   8
   9 AC_DEFUN([AC_COMPILER_CHARACTERISTICS],
  10   [AC_CACHE_CHECK(AC_PRIUS_COMMENT, ac_cv_formatting_prius_prefix,
  11     [AC_TYPES_COMPATIBLE(unsigned int, size_t,
  12                          ac_cv_formatting_prius_prefix=; ac_cv_prius_defined=1)
  13      AC_TYPES_COMPATIBLE(unsigned long, size_t,
  14                          ac_cv_formatting_prius_prefix=l; ac_cv_prius_defined=1)
  15      AC_TYPES_COMPATIBLE(unsigned long long, size_t,
  16                          ac_cv_formatting_prius_prefix=ll; ac_cv_prius_defined=1
  17      )])
  18    if test -z "$ac_cv_prius_defined"; then
  19       ac_cv_formatting_prius_prefix=z;
  20    fi
  21    AC_DEFINE_UNQUOTED(PRIuS, "${ac_cv_formatting_prius_prefix}u", AC_PRIUS_COMMENT)
  22    AC_DEFINE_UNQUOTED(PRIxS, "${ac_cv_formatting_prius_prefix}x", AC_PRIUS_COMMENT)
  23    AC_DEFINE_UNQUOTED(PRIdS, "${ac_cv_formatting_prius_prefix}d", AC_PRIUS_COMMENT)
  24 ])