+ [dnl On some systems, e.g., NetBSD 5.0 with GCC 4.1, `__thread' is
+ dnl properly compiled but fails to link due to the lack of TLS
+ dnl support in the C library. Thus we try to link, not just
+ dnl compile. Unfortunately, this test is not enough, so we
+ dnl explicitly check for known-broken systems. See
+ dnl http://lists.gnu.org/archive/html/guile-devel/2009-10/msg00138.html
+ dnl for details.
+ dnl
+ dnl Known broken systems includes:
+ dnl - x86_64-unknown-netbsd5.0.
+ dnl - sparc-sun-solaris2.8
+ case "x$enable_shared--$host" in
+ xyes--*netbsd[0-5].[0-9].|xyes--*solaris2.8)
+ ac_cv_have_thread_storage_class="no"
+ ;;
+ *)
+ AC_LINK_IFELSE([AC_LANG_PROGRAM([__thread int tls_integer;],