1 # ===========================================================================
2 # http://www.gnu.org/software/autoconf-archive/ax_tls.html
3 # ===========================================================================
7 # AX_TLS([action-if-found], [action-if-not-found])
11 # Provides a test for the compiler support of thread local storage (TLS)
12 # extensions. Defines TLS if it is found. Currently knows about GCC/ICC
13 # and MSVC. I think SunPro uses the same as GCC, and Borland apparently
18 # Copyright (c) 2008 Alan Woodland <ajw05@aber.ac.uk>
19 # Copyright (c) 2010 Diego Elio Pettenò <flameeyes@gmail.com>
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28 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
29 # Public License for more details.
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50 AC_MSG_CHECKING(for thread local storage (TLS) class)
51 AC_CACHE_VAL(ac_cv_tls, [
52 ax_tls_keywords="__thread __declspec(thread) none"
53 for ax_tls_keyword in $ax_tls_keywords; do
54 AS_CASE([$ax_tls_keyword],
55 [none], [ac_cv_tls=none ; break],
60 static ] $ax_tls_keyword [ int bar;
64 [ac_cv_tls=$ax_tls_keyword ; break],
69 AC_MSG_RESULT($ac_cv_tls)
71 AS_IF([test "$ac_cv_tls" != "none"],
72 AC_DEFINE_UNQUOTED([TLS], $ac_cv_tls, [If the compiler supports a TLS storage class define it to that here])
73 m4_ifnblank([$1], [$1]),
74 m4_ifnblank([$2], [$2])