1# =========================================================================== 2# https://www.gnu.org/software/autoconf-archive/ax_tls.html 3# =========================================================================== 4# 5# SYNOPSIS 6# 7# AX_TLS([action-if-found], [action-if-not-found]) 8# 9# DESCRIPTION 10# 11# Provides a test for the compiler support of thread local storage (TLS) 12# extensions. Defines TLS if it is found. Currently knows about C++11, 13# GCC/ICC, and MSVC. I think SunPro uses the same as GCC, and Borland 14# apparently supports either. 15# 16# LICENSE 17# 18# Copyright (c) 2008 Alan Woodland <ajw05@aber.ac.uk> 19# Copyright (c) 2010 Diego Elio Petteno` <flameeyes@gmail.com> 20# 21# This program is free software: you can redistribute it and/or modify it 22# under the terms of the GNU General Public License as published by the 23# Free Software Foundation, either version 3 of the License, or (at your 24# option) any later version. 25# 26# This program is distributed in the hope that it will be useful, but 27# WITHOUT ANY WARRANTY; without even the implied warranty of 28# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 29# Public License for more details. 30# 31# You should have received a copy of the GNU General Public License along 32# with this program. If not, see <https://www.gnu.org/licenses/>. 33# 34# As a special exception, the respective Autoconf Macro's copyright owner 35# gives unlimited permission to copy, distribute and modify the configure 36# scripts that are the output of Autoconf when processing the Macro. You 37# need not follow the terms of the GNU General Public License when using 38# or distributing such scripts, even though portions of the text of the 39# Macro appear in them. The GNU General Public License (GPL) does govern 40# all other use of the material that constitutes the Autoconf Macro. 41# 42# This special exception to the GPL applies to versions of the Autoconf 43# Macro released by the Autoconf Archive. When you make and distribute a 44# modified version of the Autoconf Macro, you may extend this special 45# exception to the GPL to apply to your modified version as well. 46 47#serial 15 48 49AC_DEFUN([AX_TLS], [ 50 AC_MSG_CHECKING([for thread local storage (TLS) class]) 51 AC_CACHE_VAL([ac_cv_tls], 52 [for ax_tls_keyword in thread_local _Thread_local __thread '__declspec(thread)' none; do 53 AS_CASE([$ax_tls_keyword], 54 [none], [ac_cv_tls=none ; break], 55 [AC_COMPILE_IFELSE([AC_LANG_PROGRAM( 56 [#include <stdlib.h>], 57 [static $ax_tls_keyword int bar;] 58 )], 59 [ac_cv_tls=$ax_tls_keyword ; break], 60 [ac_cv_tls=none] 61 )] 62 ) 63 done ] 64 ) 65 AC_MSG_RESULT([$ac_cv_tls]) 66 67 AS_IF([test "$ac_cv_tls" != "none"], 68 [AC_DEFINE_UNQUOTED([TLS],[$ac_cv_tls],[If the compiler supports a TLS storage class, define it to that here]) 69 m4_ifnblank([$1],[$1],[[:]])], 70 [m4_ifnblank([$2],[$2],[[:]])]) 71]) 72