config/

[deliverable/binutils-gdb.git] / config / tls.m4

diff --git a/config/tls.m4 b/config/tls.m4
index b6c4c4a6a7da5677506dcf92f3928c9891e311b6..79cf382066483650e2c6c7e9ba5de849deca72f5 100644 (file)
--- a/config/tls.m4
+++ b/config/tls.m4
@@ -1,5 +1,6 @@
 dnl Check whether the target supports TLS.
 AC_DEFUN([GCC_CHECK_TLS], [
+  AC_REQUIRE([AC_CANONICAL_HOST])
   GCC_ENABLE(tls, yes, [], [Use thread-local storage])
   AC_CACHE_CHECK([whether the target supports thread-local storage],
                 gcc_cv_have_tls, [
@@ -10,8 +11,8 @@ AC_DEFUN([GCC_CHECK_TLS], [
       chktls_save_LDFLAGS="$LDFLAGS"
       LDFLAGS="-static $LDFLAGS"
       AC_LINK_IFELSE([int main() { return 0; }],
-       AC_RUN_IFELSE([__thread int a; int b; int main() { return a = b; }],
-                     [gcc_cv_have_tls=yes], [gcc_cv_have_tls=no],[]),
+       [AC_RUN_IFELSE([__thread int a; int b; int main() { return a = b; }],
+                      [gcc_cv_have_tls=yes], [gcc_cv_have_tls=no],[])],
        [gcc_cv_have_tls=yes])
       LDFLAGS="$chktls_save_LDFLAGS"
       if test $gcc_cv_have_tls = yes; then
@@ -66,7 +67,24 @@ AC_DEFUN([GCC_CHECK_TLS], [
       [dnl This is the cross-compiling case. Assume libc supports TLS if the
        dnl binutils and the compiler do.
        AC_LINK_IFELSE([__thread int a; int b; int main() { return a = b; }],
-                     [gcc_cv_have_tls=yes], [gcc_cv_have_tls=no])
+        [chktls_save_LDFLAGS="$LDFLAGS"
+         dnl Shared library options may depend on the host; this check
+         dnl is only known to be needed for GNU/Linux.
+         case $host in
+           *-*-linux*)
+             LDFLAGS="-shared -Wl,--no-undefined $LDFLAGS"
+             ;;
+         esac
+         chktls_save_CFLAGS="$CFLAGS"
+         CFLAGS="-fPIC $CFLAGS"
+         dnl If -shared works, test if TLS works in a shared library.
+         AC_LINK_IFELSE([int f() { return 0; }],
+           [AC_LINK_IFELSE([__thread int a; int b; int f() { return a = b; }],
+             [gcc_cv_have_tls=yes],
+             [gcc_cv_have_tls=no])],
+           [gcc_cv_have_tls=yes])
+         CFLAGS="$chktls_save_CFLAGS"
+         LDFLAGS="$chktls_save_LDFLAGS"], [gcc_cv_have_tls=no])
       ]
     )])
   if test "$enable_tls $gcc_cv_have_tls" = "yes yes"; then
@@ -77,7 +95,7 @@ AC_DEFUN([GCC_CHECK_TLS], [
 dnl Check whether the target assembler supports TLS.
 AC_DEFUN([GCC_CHECK_CC_TLS], [
   GCC_ENABLE(tls, yes, [], [Use thread-local storage])
-  AC_CACHE_CHECK([whether the target asssembler upports thread-local storage],
+  AC_CACHE_CHECK([whether the target assembler supports thread-local storage],
                 gcc_cv_have_cc_tls, [
     AC_COMPILE_IFELSE([__thread int a; int b; int main() { return a = b; }],
       [gcc_cv_have_cc_tls=yes], [gcc_cv_have_cc_tls=no])]