 GCC 5.5.0 (2017) cannot be built out-of-the-box by g++/GCC 11.3.0 (2022) because g++ 11.x defaults to C++17, whereas GCC 5.5 expects C++11, which apparently has incompatible features/semantics in some places. Thanks again to the bright minds who pushed for C++ in GCC (and then left). 9 comments
 @sevan @civodul If you are using #libtool, you should use CXX='g++ -std=c++11' because if it’s a CXXFLAG, libtool will remove it. https://www.gnu.org/software/libtool/manual/libtool.html#Stripped-link-flags @gugurumbe @civodul I guess in this scenario you have a GCC 5.x release archive uncompressed and you're just trying to build it with new GCC, the release archive is already bootstrapped with autoconf so you're not regenerating the build infra needing libtool to be re-run? @sevan I don’t know if GCC 5.x uses libtool, but if it does, then it’s a compile-time, not bootstrap, thing. @mjw That’s the idea but there are complications in the GCC packaging in Guix (it’ll soon be time for Spring cleanup!). |
Gregory's Server
@civodul is it not possible to pass -std=gnu++11 to g++ if it's v11.x?