Update macros from the autotools archive
[urcu.git] / m4 / ax_tls.m4
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 14
48
49 AC_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_TRY_COMPILE(
56 [#include <stdlib.h>
57 static void
58 foo(void) {
59 static ] $ax_tls_keyword [ int bar;
60 exit(1);
61 }],
62 [],
63 [ac_cv_tls=$ax_tls_keyword ; break],
64 ac_cv_tls=none
65 )])
66 done
67 ])
68 AC_MSG_RESULT([$ac_cv_tls])
69
70 AS_IF([test "$ac_cv_tls" != "none"],
71 [AC_DEFINE_UNQUOTED([TLS],[$ac_cv_tls],[If the compiler supports a TLS storage class define it to that here])
72 m4_ifnblank([$1],[$1])],
73 [m4_ifnblank([$2],[$2])])
74 ])
This page took 0.036276 seconds and 5 git commands to generate.