http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54806
--- Comment #14 from Jack Howarth <howarth at nitro dot med.uc.edu> 2012-10-06 17:00:17 UTC --- Interestingly Macports' libgomp shows the same expected emutls related symbols as fink... % nm libgomp.1.dylib | grep emutls U ___emutls_get_address 000000000000b1e0 d ___emutls_v.gomp_tls_data I suspect the absence of ___emutls_v.* symbols in the MacPorts gcc47's libstdc++.6.dylib could be due to the fact that clang is used to build it rather than a proper full bootstrap. Please try restoring the bootstrap and see if the symbols are restored to libstdc++.6.dylib.