# mode_t.m4 serial 2

dnl Copyright (C) 2009-2020 Free Software Foundation, Inc.

dnl This file is free software; the Free Software Foundation

dnl gives unlimited permission to copy and/or distribute it,

dnl with or without modifications, as long as this notice is preserved.

# For using mode_t, it's sufficient to use AC_TYPE_MODE_T and

# include <sys/types.h>.

# Define PROMOTED_MODE_T to the type that is the result of "default argument

# promotion" (ISO C 6.5.2.2.(6)) of the type mode_t.

AC_DEFUN([gl_PROMOTED_TYPE_MODE_T],

[

  AC_REQUIRE([AC_TYPE_MODE_T])

  AC_CACHE_CHECK([for promoted mode_t type], [gl_cv_promoted_mode_t], [

    dnl Assume mode_t promotes to 'int' if and only if it is smaller than 'int',

    dnl and to itself otherwise. This assumption is not guaranteed by the ISO C

    dnl standard, but we don't know of any real-world counterexamples.

    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/types.h>]],

      [[typedef int array[2 * (sizeof (mode_t) < sizeof (int)) - 1];]])],

      [gl_cv_promoted_mode_t='int'],

      [gl_cv_promoted_mode_t='mode_t'])

  ])

  AC_DEFINE_UNQUOTED([PROMOTED_MODE_T], [$gl_cv_promoted_mode_t],

    [Define to the type that is the result of default argument promotions of type mode_t.])

])