Ping Re: Improve TLS link test for cross-compiling
Joseph S. Myers
joseph@codesourcery.com
Fri Jul 17 00:19:00 GMT 2009
On Tue, 14 Jul 2009, Paolo Bonzini wrote:
> On 07/14/2009 05:41 PM, Joseph S. Myers wrote:
> > Ping. This patch
> > <http://gcc.gnu.org/ml/gcc-patches/2009-07/msg00139.html> is pending
> > review.
>
> Are there any targets that support TLS but use anything but -shared to link a
> shared library, or that do not have -Wl,--no-undefined? I'm thinking of
> Solaris with Sun as and ld especially.
>
> Okay if you conditionalize setting the LDFLAGS on $host being *-*-linux*
> (don't know about uclinux?) and require AC_CANONICAL_HOST at the top of the
> file.
I have applied this patch with that condition added.
config:
2009-07-16 Joseph Myers <joseph@codesourcery.com>
* tls.m4 (GCC_CHECK_TLS): Also test TLS in a shared library when
cross-compiling.
libgomp:
2009-07-16 Joseph Myers <joseph@codesourcery.com>
* configure: Regenerate.
libjava:
2009-07-16 Joseph Myers <joseph@codesourcery.com>
* configure: Regenerate.
libmudflap:
2009-07-16 Joseph Myers <joseph@codesourcery.com>
* configure: Regenerate.
libstdc++-v3:
2009-07-16 Joseph Myers <joseph@codesourcery.com>
* configure: Regenerate.
Index: config/tls.m4
===================================================================
--- config/tls.m4 (revision 149722)
+++ config/tls.m4 (working copy)
@@ -1,5 +1,6 @@
dnl Check whether the target supports TLS.
AC_DEFUN([GCC_CHECK_TLS], [
+ AC_REQUIRE([AC_CANONICAL_HOST])
GCC_ENABLE(tls, yes, [], [Use thread-local storage])
AC_CACHE_CHECK([whether the target supports thread-local storage],
gcc_cv_have_tls, [
@@ -66,7 +67,24 @@
[dnl This is the cross-compiling case. Assume libc supports TLS if the
dnl binutils and the compiler do.
AC_LINK_IFELSE([__thread int a; int b; int main() { return a = b; }],
- [gcc_cv_have_tls=yes], [gcc_cv_have_tls=no])
+ [chktls_save_LDFLAGS="$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
--
Joseph S. Myers
joseph@codesourcery.com
More information about the Java-patches
mailing list