[Bug libstdc++/118811] SIGABRT (or ASAN heap-use-after-free) in chrono::locate_zone--chrono::tzdb_list during exit handlers

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118811

--- Comment #13 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Unrelated to the lifetime bug, but why not just use utc_clock here?

  auto timestamp( std::chrono::duration_cast< std::chrono::nanoseconds >(
    std::chrono::system_clock::now().time_since_epoch() ) );
  std::chrono::zoned_time zt(
    "UTC",
    std::chrono::time_point_cast< std::chrono::microseconds >(
      std::chrono::sys_time< std::chrono::nanoseconds >( timestamp ) ) );
  return std::format( "{:%Y-%m-%dT%TZ}", zt );


Why not simply:

  auto ut = std::chrono::utc_clock::now();
  auto mut = std::chrono::time_point_cast<std::chrono::microseconds>(ut);
  return std::format( "{:%Y-%m-%dT%TZ}", mut );

?