diff options
Diffstat (limited to 'config/tls.m4')
| -rw-r--r-- | config/tls.m4 | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/config/tls.m4 b/config/tls.m4 index 79cf382..ef7e6d0 100644 --- a/config/tls.m4 +++ b/config/tls.m4 @@ -104,3 +104,21 @@ AC_DEFUN([GCC_CHECK_CC_TLS], [ AC_DEFINE(HAVE_CC_TLS, 1, [Define to 1 if the target assembler supports thread-local storage.]) fi]) + +dnl Check whether TLS is emulated. +AC_DEFUN([GCC_CHECK_EMUTLS], [ + AC_CACHE_CHECK([whether the thread-local storage support is from emutls], + gcc_cv_use_emutls, [ + gcc_cv_use_emutls=no + echo '__thread int a; int b; int main() { return a = b; }' > conftest.c + if AC_TRY_COMMAND(${CC-cc} -Werror -S -o conftest.s conftest.c 1>&AS_MESSAGE_LOG_FD); then + if grep __emutls_get_address conftest.s > /dev/null; then + gcc_cv_use_emutls=yes + fi + fi + rm -f conftest.* + ]) + if test "$gcc_cv_use_emutls" = "yes" ; then + AC_DEFINE(USE_EMUTLS, 1, + [Define to 1 if the target use emutls for thread-local storage.]) + fi]) |