Fix to prevent compiler optimizations

from bug #30

diff --git a/acinclude.m4 b/acinclude.m4
index 5043e2b..1dd8ad1 100644 (file)
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -383,7 +383,7 @@ m4_pushdef([AC_OUTPUT],
 AC_DEFUN([FR_TLS],
 [
     AC_MSG_CHECKING(for TLS)
-    AC_RUN_IFELSE([AC_LANG_SOURCE([[ static __thread int val; int main() { return 0; } ]])],[have_tls=yes],[have_tls=no],[have_tls=no ])
+    AC_RUN_IFELSE([AC_LANG_SOURCE([[ static __thread int val; int main(int argc, char *argv[]) { return val = argc; } ]])],[have_tls=yes],[have_tls=no],[have_tls=no ])
     AC_MSG_RESULT($have_tls)
     if test "$have_tls" = "yes"; then
         AC_DEFINE([HAVE_THREAD_TLS],[1],[Define if the compiler supports __thread])