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Diffstat (limited to 'gcc-4.2.1/config/tls.m4')
| -rw-r--r-- | gcc-4.2.1/config/tls.m4 | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/gcc-4.2.1/config/tls.m4 b/gcc-4.2.1/config/tls.m4 new file mode 100644 index 000000000..f1e11a06c --- /dev/null +++ b/gcc-4.2.1/config/tls.m4 @@ -0,0 +1,23 @@ +dnl Check whether the target supports TLS. +AC_DEFUN([GCC_CHECK_TLS], [ + GCC_ENABLE(tls, yes, [], [Use thread-local storage]) + AC_CACHE_CHECK([whether the target supports thread-local storage], + have_tls, [ + AC_RUN_IFELSE([__thread int a; int b; int main() { return a = b; }], + [dnl If the test case passed with dynamic linking, try again with + dnl static linking, but only if static linking is supported (not + dnl on Solaris 10). This fails with some older Red Hat releases. + save_LDFLAGS="$LDFLAGS" + LDFLAGS="-static $LDFLAGS" + AC_LINK_IFELSE([int main() { return 0; }], + AC_RUN_IFELSE([__thread int a; int b; int main() { return a = b; }], + [have_tls=yes], [have_tls=no],[]), + [have_tls=yes]) + LDFLAGS="$save_LDFLAGS"], + [have_tls=no], + [AC_COMPILE_IFELSE([__thread int foo;], [have_tls=yes], [have_tls=no])] + )]) + if test "$enable_tls $have_tls" = "yes yes"; then + AC_DEFINE(HAVE_TLS, 1, + [Define to 1 if the target supports thread-local storage.]) + fi]) |