[PATCH] gnulib-common.m4: add _GL_ATTRIBUTE_CONST and _GL_ATTRIBUTE_PURE

[Jim Meyering]

FYI, as discussed, here are the definitions.
I'll be adding uses separately, in headers when possible.

>From dd36104845e77faa713653d1173623a20082cc76 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Sun, 24 Apr 2011 19:00:18 +0200
Subject: [PATCH] gnulib-common.m4: add _GL_ATTRIBUTE_CONST and
 _GL_ATTRIBUTE_PURE

* m4/gnulib-common.m4 (gl_COMMON): Emit definitions of
_GL_ATTRIBUTE_CONST and _GL_ATTRIBUTE_PURE.
---
 ChangeLog           |    6 ++++++
 m4/gnulib-common.m4 |   16 +++++++++++++++-
 2 files changed, 21 insertions(+), 1 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1190e1d..57d8da4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2011-06-06  Jim Meyering  <address@hidden>
+
+       gnulib-common.m4: add _GL_ATTRIBUTE_CONST and _GL_ATTRIBUTE_PURE
+       * m4/gnulib-common.m4 (gl_COMMON): Emit definitions of
+       _GL_ATTRIBUTE_CONST and _GL_ATTRIBUTE_PURE.
+
 2011-06-05  Bruno Haible  <address@hidden>

        ansi-c++-opt: Interoperability with libtool.
diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4
index c4d7a20..8b73f1d 100644
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@@ -1,4 +1,4 @@
-# gnulib-common.m4 serial 24
+# gnulib-common.m4 serial 25
 dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -34,6 +34,20 @@ AC_DEFUN([gl_COMMON_BODY], [
 /* The name _UNUSED_PARAMETER_ is an earlier spelling, although the name
    is a misnomer outside of parameter lists.  */
 #define _UNUSED_PARAMETER_ _GL_UNUSED
+
+/* The __pure__ attribute was added in gcc 2.96.  */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+#else
+# define _GL_ATTRIBUTE_PURE /* empty */
+#endif
+
+/* The __const__ attribute was added in gcc 2.95.  */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
+# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
+#else
+# define _GL_ATTRIBUTE_CONST /* empty */
+#endif
 ])
   dnl Preparation for running test programs:
   dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
--
1.7.6.rc0.254.gf37de