https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119550
--- Comment #10 from Jonathan Wakely <redi at gcc dot gnu.org> --- N.B. this intentionally replaces _GLIBCXX_HAVE_STRUCT_TM_TM_ZONE with _GLIBCXX_USE_STRUCT_TM_TM_ZONE because the latter "USE" macro is not going to collide with the one from autoconf, in case that gets re-added at a later date. This requires a small change to the use of the macro in include/bits/chrono_io.h obviously.
