[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 #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Oh, (void*)1 works, it's only rejected with the LL suffix. That's not
conforming either (and Clang rejects it).