# minmax.m4 serial 4

dnl Copyright (C) 2005, 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.

AC_PREREQ([2.53])

AC_DEFUN([gl_MINMAX],

[

  AC_REQUIRE([gl_PREREQ_MINMAX])

])

# Prerequisites of lib/minmax.h.

AC_DEFUN([gl_PREREQ_MINMAX],

[

  gl_MINMAX_IN_HEADER([limits.h])

  gl_MINMAX_IN_HEADER([sys/param.h])

])

dnl gl_MINMAX_IN_HEADER(HEADER)

dnl The parameter has to be a literal header name; it cannot be macro,

dnl nor a shell variable. (Because autoheader collects only AC_DEFINE

dnl invocations with a literal macro name.)

AC_DEFUN([gl_MINMAX_IN_HEADER],

[

  m4_pushdef([header], AS_TR_SH([$1]))

  m4_pushdef([HEADER], AS_TR_CPP([$1]))

  AC_CACHE_CHECK([whether <$1> defines MIN and MAX],

    [gl_cv_minmax_in_]header,

    [AC_COMPILE_IFELSE(

       [AC_LANG_PROGRAM(

          [[#include <$1>

            int x = MIN (42, 17);]],

          [[]])],

       [gl_cv_minmax_in_]header[=yes],

       [gl_cv_minmax_in_]header[=no])])

  if test $gl_cv_minmax_in_[]header = yes; then

    AC_DEFINE([HAVE_MINMAX_IN_]HEADER, 1,

      [Define to 1 if <$1> defines the MIN and MAX macros.])

  fi

  m4_popdef([HEADER])

  m4_popdef([header])

])