# -*- Autoconf -*-
#
# This file is from Autoconf 2.61, for compatibility with older
# Autoconfs.  Original copyright below.
# Remove this file when we drop support for AC 2.59 and older

# This file is part of Autoconf.			-*- Autoconf -*-
# Macros that test for specific, unclassified, features.
#
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# 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
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# along with this program; if not, write to the Free Software
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# 02110-1301, USA.
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# Autoconf.  We call these the "data" portions.  The rest of the Autoconf
# source text consists of comments plus executable code that decides which
# of the data portions to output in any given case.  We call these
# comments and executable code the "non-data" portions.  Autoconf never
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#
# Written by David MacKenzie, with help from
# Franc,ois Pinard, Karl Berry, Richard Pixley, Ian Lance Taylor,
# Roland McGrath, Noah Friedman, david d zuhn, and many others.

# AC_USE_SYSTEM_EXTENSIONS
# ------------------------
# Enable extensions on systems that normally disable them,
# typically due to standards-conformance issues.
AC_DEFUN([AC_USE_SYSTEM_EXTENSIONS],
[
  AC_BEFORE([$0], [AC_COMPILE_IFELSE])
  AC_BEFORE([$0], [AC_RUN_IFELSE])

  AC_REQUIRE([AC_GNU_SOURCE])
  AC_REQUIRE([AC_AIX])
  AC_REQUIRE([AC_MINIX])

  AH_VERBATIM([__EXTENSIONS__],
[/* Enable extensions on Solaris.  */
#ifndef __EXTENSIONS__
# undef __EXTENSIONS__
#endif
#ifndef _POSIX_PTHREAD_SEMANTICS
# undef _POSIX_PTHREAD_SEMANTICS
#endif
#ifndef _TANDEM_SOURCE
# undef _TANDEM_SOURCE
#endif])
  AC_CACHE_CHECK([whether it is safe to define __EXTENSIONS__],
    [ac_cv_safe_to_define___extensions__],
    [AC_COMPILE_IFELSE(
       [AC_LANG_PROGRAM([
#	  define __EXTENSIONS__ 1
	  AC_INCLUDES_DEFAULT])],
       [ac_cv_safe_to_define___extensions__=yes],
       [ac_cv_safe_to_define___extensions__=no])])
  test $ac_cv_safe_to_define___extensions__ = yes &&
    AC_DEFINE([__EXTENSIONS__])
  AC_DEFINE([_POSIX_PTHREAD_SEMANTICS])
  AC_DEFINE([_TANDEM_SOURCE])
])
