https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71541
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- You need to link to libpthread to use std::condition_variable_any.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71541
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- You need to link to libpthread to use std::condition_variable_any.