https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70493
--- Comment #1 from Michi Henning <michi at triodia dot com> --- Ah, on reading http://pubs.opengroup.org/onlinepubs/9699919799/ section 8.2, it appears that it's OK to throw in this case. It would be nice to have a better diagnostic in the exception though. It could show the facet that was found to be bad and the value that was objectionable maybe?
