Eric Blake wrote:
> > m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]),[2.62]),[-1],
> > [AC_REQUIRE([AC_GNU_SOURCE])],
> > [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])])
>
> Why not the simpler:
>
> m4_ifndef([AC_USE_SYSTEM_EXTENSIONS],
> [AC_DEFUN([AC_USE_SYSTEM_EXTENSIONS], [AC_GNU_SOURCE])])
After verifying that AC_USE_SYSTEM_EXTENSIONS subsumed AC_GNU_SOURCE from
the beginning, this is as good. Indeed, no need to use m4_PACKAGE_VERSION
in this case.
> ***************
> *** 35,41 ****
> AC_BEFORE([$0], [gl_ARGP])dnl
>
> AC_REQUIRE([AC_CANONICAL_HOST])
> ! AC_REQUIRE([AC_GNU_SOURCE]) dnl needed for pthread_rwlock_t on glibc
> systems
> dnl Check for multithreading.
> AC_ARG_ENABLE(threads,
> AC_HELP_STRING([--enable-threads={posix|solaris|pth|win32}], [specify
> multithreading API])
> --- 35,41 ----
> AC_BEFORE([$0], [gl_ARGP])dnl
>
> AC_REQUIRE([AC_CANONICAL_HOST])
> ! AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS]) dnl needed for pthread_rwlock_t on
> glibc systems
> dnl Check for multithreading.
> AC_ARG_ENABLE(threads,
> AC_HELP_STRING([--enable-threads={posix|solaris|pth|win32}], [specify
> multithreading API])
> ***************
> *** 257,262 ****
> --- 257,270 ----
> AC_REQUIRE([AC_C_INLINE])
> ])
>
> + # AC_USE_SYSTEM_EXTENSIONS was only added in autoconf 2.60, but lock.m4
> + # wants to work with autoconf 2.54. Add a fallback until such time as
> + # a newer autoconf is standard, if one is not already provided by gnulib
> + # extensions.m4.
> + m4_if(m4_version_compare(m4_PACKAGE_VERSION, [2.60]), [-1],
> + [m4_ifndef([AC_USE_SYSTEM_EXTENSIONS],
> + [AC_DEFUN([AC_USE_SYSTEM_EXTENSIONS], [AC_GNU_SOURCE])])])
> +
> dnl Survey of platforms:
> dnl
> dnl Platform Available Compiler Supports test-lock
This is more fragile than a simple 'ifdef'. I don't want gettext's lock.m4
to compete with gnulib's extensions.m4 - otherwise it means that in some
circumstances, gnulib's extensions.m4 will not work. Changing it like this:
2007-09-12 Bruno Haible <[EMAIL PROTECTED]>
* m4/lock.m4: Don't provide an AC_USE_SYSTEM_EXTENSIONS definition.
(gl_LOCK_EARLY_BODY): Use AC_GNU_SOURCE when AC_USE_SYSTEM_EXTENSIONS
is not defined.
--- m4/lock.m4 12 Sep 2007 15:59:57 -0000 1.10
+++ m4/lock.m4 12 Sep 2007 23:22:42 -0000
@@ -1,4 +1,4 @@
-# lock.m4 serial 7 (gettext-0.16)
+# lock.m4 serial 7 (gettext-0.16.2)
dnl Copyright (C) 2005-2007 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -35,7 +35,12 @@
AC_BEFORE([$0], [gl_ARGP])dnl
AC_REQUIRE([AC_CANONICAL_HOST])
- AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS]) dnl needed for pthread_rwlock_t on
glibc systems
+ dnl _GNU_SOURCE is needed for pthread_rwlock_t on glibc systems.
+ dnl AC_USE_SYSTEM_EXTENSIONS was introduced in autoconf 2.60 and obsoletes
+ dnl AC_GNU_SOURCE.
+ m4_ifdef([AC_USE_SYSTEM_EXTENSIONS],
+ [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])],
+ [AC_REQUIRE([AC_GNU_SOURCE])])
dnl Check for multithreading.
AC_ARG_ENABLE(threads,
AC_HELP_STRING([--enable-threads={posix|solaris|pth|win32}], [specify
multithreading API])
@@ -257,14 +262,6 @@
AC_REQUIRE([AC_C_INLINE])
])
-# AC_USE_SYSTEM_EXTENSIONS was only added in autoconf 2.60, but lock.m4
-# wants to work with autoconf 2.54. Add a fallback until such time as
-# a newer autoconf is standard, if one is not already provided by gnulib
-# extensions.m4.
-m4_if(m4_version_compare(m4_PACKAGE_VERSION, [2.60]), [-1],
- [m4_ifndef([AC_USE_SYSTEM_EXTENSIONS],
- [AC_DEFUN([AC_USE_SYSTEM_EXTENSIONS], [AC_GNU_SOURCE])])])
-
dnl Survey of platforms:
dnl
dnl Platform Available Compiler Supports test-lock
