https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81806
--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Oleksandr Kulkov from comment #5) > 1. At least, Jonathan suggested to start with fixing this in > https://gcc.gnu.org/ml/libstdc++/2019-07/msg00066.html , so it doesn't seem > hopeless for now I think ABI breaks in pb_ds are OK. If necessary we can use an inline namespace to mangle the fixed types differently. > 4. Even so is better than having it non-fixed or even deprecated forever Right. If you only care about the Ubuntu version used in contests, that already has pb_ds, so you wouldn't care if we removed it upstream, right? ;-)