Commit 93393411 authored by Thomas Fogal's avatar Thomas Fogal Committed by Dan Nicholson

Add macro for detecting thread local storage support.

This adds an AX_TLS macro which attempts to identify if the
underlying compiler/platform supports thread local storage (TLS).
The macro comes from the autoconf macro archive.
Signed-off-by: Thomas Fogal's avatarTom Fogal <tfogal@alumni.unh.edu>
Reviewed-by: Dan Nicholson's avatarDan Nicholson <dbn.lists@gmail.com>
parent 60801ff8
# ===========================================================================
# http://www.nongnu.org/autoconf-archive/ax_tls.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_TLS
#
# DESCRIPTION
#
# Provides a test for the compiler support of thread local storage (TLS)
# extensions. Defines TLS if it is found. Currently only knows about GCC
# 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>
#
# 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.
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
case $ax_tls_keyword in
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
)
esac
done
])
if test "$ac_cv_tls" != "none"; then
dnl AC_DEFINE([TLS], [], [If the compiler supports a TLS storage class define it to that here])
AC_DEFINE_UNQUOTED([TLS], $ac_cv_tls, [If the compiler supports a TLS storage class define it to that here])
fi
AC_MSG_RESULT($ac_cv_tls)
])
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment