https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81806
--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Xi Ruoyao from comment #7) > Oh I didn't expect an ABI breakage. I thought "pb_ds is a source code > library so there is no ABI in libstdc++.so". Now I understand that we > should not break old third-party libraries compiled with the old pb_ds > headers (is there any? :) The libstdc++ ABI is larger than the set of symbols exported from libstdc++.so std::vector is defined entirely in headers, not exported from libstdc++.so, but we can't just change its layout. That would make it impossible to link objects compiled with different versions of GCC because they would disagree on the layout of std::vector. So this isn't about third-party libraries, it's about all code that uses pb_ds. If you compile foo.o with one version of GCC and bar.o with another version of GCC, then you should be able to link them together.
