New module 'frexpl-nolibm'.

[gnulib.git] / m4 / extensions.m4

diff --git a/m4/extensions.m4 b/m4/extensions.m4
index 4976079..143a9e5 100644 (file)
--- a/m4/extensions.m4
+++ b/m4/extensions.m4
@@ -1,3 +1,4 @@
+# serial 4  -*- Autoconf -*-
 # Enable extensions on systems that normally disable them.
 
 # Copyright (C) 2003, 2006 Free Software Foundation, Inc.
@@ -5,14 +6,18 @@
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 
-# This file is only needed in autoconf <= 2.59.  Newer versions of autoconf
-# have a macro AC_USE_SYSTEM_EXTENSIONS with identical semantics.
+# 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])
 
@@ -27,16 +32,27 @@ AC_DEFUN([gl_USE_SYSTEM_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
+#        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])])