diff options
Diffstat (limited to 'm4/xorg-tls.m4')
| -rw-r--r-- | m4/xorg-tls.m4 | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/m4/xorg-tls.m4 b/m4/xorg-tls.m4 new file mode 100644 index 000000000..563850420 --- /dev/null +++ b/m4/xorg-tls.m4 @@ -0,0 +1,57 @@ +dnl Copyright © 2011 Apple Inc. +dnl +dnl Permission is hereby granted, free of charge, to any person obtaining a +dnl copy of this software and associated documentation files (the "Software"), +dnl to deal in the Software without restriction, including without limitation +dnl the rights to use, copy, modify, merge, publish, distribute, sublicense, +dnl and/or sell copies of the Software, and to permit persons to whom the +dnl Software is furnished to do so, subject to the following conditions: +dnl +dnl The above copyright notice and this permission notice (including the next +dnl paragraph) shall be included in all copies or substantial portions of the +dnl Software. +dnl +dnl THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +dnl IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +dnl FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL +dnl THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +dnl LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING +dnl FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +dnl DEALINGS IN THE SOFTWARE. +dnl +dnl Authors: Jeremy Huddleston <jeremyhu@apple.com> + +AC_DEFUN([XORG_TLS], [ + AC_MSG_CHECKING(for thread local storage (TLS) support) + AC_CACHE_VAL(ac_cv_tls, [ + ac_cv_tls=none + keywords="__thread __declspec(thread)" + for kw in $keywords ; do + AC_TRY_COMPILE([int $kw test;], [], ac_cv_tls=$kw) + done + ]) + AC_MSG_RESULT($ac_cv_tls) + + if test "$ac_cv_tls" != "none"; then + AC_MSG_CHECKING(for tls_model attribute support) + AC_CACHE_VAL(ac_cv_tls_model, [ + save_CFLAGS="$CFLAGS" + dnl -Werror causes clang's default -Wunknown-attributes to become an error + dnl We can't use -Werror=unknown-attributes because gcc doesn't understand it + dnl -Werror=attributes is for gcc, clang seems to ignore it + CFLAGS="$CFLAGS -Werror -Werror=attributes" + AC_TRY_COMPILE([int $ac_cv_tls __attribute__((tls_model("initial-exec"))) test;], [], + ac_cv_tls_model=yes, ac_cv_tls_model=no) + CFLAGS="$save_CFLAGS" + ]) + AC_MSG_RESULT($ac_cv_tls_model) + + if test "x$ac_cv_tls_model" = "xyes" ; then + xorg_tls=$ac_cv_tls' __attribute__((tls_model("initial-exec")))' + else + xorg_tls=$ac_cv_tls + fi + + AC_DEFINE_UNQUOTED([TLS], $xorg_tls, [The compiler supported TLS storage class, prefering initial-exec if tls_model is supported]) + fi +]) |