blob: 3f6b5e10ba4cee862626b18cb6a7614aa8c55e58 [file] [log] [blame]
# ===========================================================================
# http://www.gnu.org/software/autoconf-archive/ax_tls.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_TLS([action-if-found], [action-if-not-found])
#
# DESCRIPTION
#
# Provides a test for the compiler support of thread local storage (TLS)
# extensions. Defines TLS if it is found. Currently knows about GCC/ICC
# and MSVC. I think SunPro uses the same as GCC, and Borland apparently
# supports either.
#
# LICENSE
#
# Copyright (c) 2008 Alan Woodland <ajw05@aber.ac.uk>
# Copyright (c) 2010 Diego Elio Petteno` <flameeyes@gmail.com>
#
# 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 3 of the License, or (at your
# option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program. If not, see <http://www.gnu.org/licenses/>.
#
# As a special exception, the respective Autoconf Macro's copyright owner
# gives unlimited permission to copy, distribute and modify the configure
# scripts that are the output of Autoconf when processing the Macro. You
# need not follow the terms of the GNU General Public License when using
# or distributing such scripts, even though portions of the text of the
# Macro appear in them. The GNU General Public License (GPL) does govern
# all other use of the material that constitutes the Autoconf Macro.
#
# This special exception to the GPL applies to versions of the Autoconf
# Macro released by the Autoconf Archive. When you make and distribute a
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
#serial 11
# Define m4_ifblank and m4_ifnblank macros from introduced in
# autotools 2.64 m4sugar.m4 if using an earlier autotools.
ifdef([m4_ifblank], [], [
m4_define([m4_ifblank],
[m4_if(m4_translit([[$1]], [ ][ ][
]), [], [$2], [$3])])
])
ifdef([m4_ifnblank], [], [
m4_define([m4_ifnblank],
[m4_if(m4_translit([[$1]], [ ][ ][
]), [], [$3], [$2])])
])
AC_DEFUN([AX_TLS], [
AC_MSG_CHECKING(for thread local storage (TLS) class)
AC_CACHE_VAL(ac_cv_tls, [
ax_tls_keywords="__thread __declspec(thread) none"
for ax_tls_keyword in $ax_tls_keywords; do
AS_CASE([$ax_tls_keyword],
[none], [ac_cv_tls=none ; break],
[AC_TRY_COMPILE(
[#include <stdlib.h>
static void
foo(void) {
static ] $ax_tls_keyword [ int bar;
exit(1);
}],
[],
[ac_cv_tls=$ax_tls_keyword ; break],
ac_cv_tls=none
)])
done
])
AC_MSG_RESULT($ac_cv_tls)
AS_IF([test "$ac_cv_tls" != "none"],
AC_DEFINE_UNQUOTED([TLS], $ac_cv_tls, [If the compiler supports a TLS storage class define it to that here])
m4_ifnblank([$1], [$1]),
m4_ifnblank([$2], [$2])
)
])