[Bug libstdc++/68739] FAIL: 30_threads/call_once/constexpr.cc (test for excess errors)

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68739

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #4)
> (I'll report that as a front-end bug).

Bug 79592