http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45693 --- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-09-27 18:14:21 UTC --- >After it, libstdc++-v3/configure incorrectly concludes that alpha-dec-osf5.1 has TLS support. No it should be detected that way as it has emulated TLS support.