https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91394
--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> --- Some programs which happen to not use any new features might work with an older version of libstdc++.so but that is not guaranteed, and definitely not supported. Removing one or two functions from a header is not going to solve the problem in the general case. Using _GLIBCXX_USE_CXX11_ABI is also not a solution for this, that's not what it's for. If you want to run with the libstdc++.so from GCC 4.9.4 then compile with GCC 4.9.4, that's guaranteed to work.
