https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65923
--- Comment #9 from Tony E Lewis <TonyELewis at hotmail dot com> --- I'm so delighted to see: #include <chrono> #include <string> using std::literals::chrono_literals::operator""s; using std::literals::string_literals::operator""s; ...compiling cleaning on Godbolt. Thanks for this Ville.