[arch-dev-public] C++ ABI bump rebuild

Hi everyone, GCC-5.x release libstdc++ with a dual ABI [1]. The time has come to rebuild everything C++ related to the new one! This means: - do not use [staging] for anything else - do not update anything C++ until it is done - help fixing anything that does not build... We will use foutrelis rebuild tool to do the building. This means TUs can not help building (the tool does not separate out [community] from [core] and [extra] yet), but you can fix build failures. Keep an eye on [2] for the build status. The build will start as soon as I get gcc ready. [1] https://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html [2] https://rebuilds.foutrelis.com/ Allan