+# serial 4 -*- Autoconf -*-
# Enable extensions on systems that normally disable them.
-# Copyright (C) 2003 Free Software Foundation, Inc.
+# Copyright (C) 2003, 2006 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
-# This file is free software, distributed under the terms of the GNU
-# General Public License. As a special exception to the GNU General
-# Public License, this file may be distributed as part of a program
-# that contains a configuration script generated by Autoconf, under
-# the same distribution terms as the rest of that program.
+# This definition of AC_USE_SYSTEM_EXTENSIONS is stolen from CVS
+# Autoconf. Perhaps we can remove this once we can assume Autoconf
+# 2.61 or later everywhere, but since CVS Autoconf mutates rapidly
+# enough in this area it's likely we'll need to redefine
+# AC_USE_SYSTEM_EXTENSIONS for quite some time.
-# gl_USE_SYSTEM_EXTENSIONS
+# AC_USE_SYSTEM_EXTENSIONS
# ------------------------
# Enable extensions on systems that normally disable them,
# typically due to standards-conformance issues.
-AC_DEFUN([gl_USE_SYSTEM_EXTENSIONS], [
+AC_DEFUN([AC_USE_SYSTEM_EXTENSIONS],
+[
AC_BEFORE([$0], [AC_COMPILE_IFELSE])
AC_BEFORE([$0], [AC_RUN_IFELSE])
[/* 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_DEFINE([__EXTENSIONS__])
+ 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])
])
+
+# gl_USE_SYSTEM_EXTENSIONS
+# ------------------------
+# Enable extensions on systems that normally disable them,
+# typically due to standards-conformance issues.
+AC_DEFUN([gl_USE_SYSTEM_EXTENSIONS],
+ [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])])