https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116657
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Toolybird from comment #0) > With tzdata-2024a it correctly prints the local timezone. With tzdata-2024b > it displays "Etc/UTC" I can't reproduce this. Adding this line to your program shows I'm using the new data: std::cout << std::chrono::get_tzdb().version << "\n"; Europe/London 2024b The libstdc++ parser is not affected by the "April" string, because we only examine as many characters as needed to unambiguously determine the month. After seeing "Ap" we skip the rest of the word, so it doesn't matter if it's "Apr" or "April" or "Apruary". (There is a bug where matching is case sensitive, so "apr" and "monday" would fail to parse, which I am already testing a patch for)