https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97358
--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
If what clang++ does with the copy ctors is right, then what firefox does is
inefficient and
[aSpecialValueMappers](const SpecialConstant<S>& aSpecialValue) {
return ErrorResult{aSpecialValueMappers(aSpecialValue)};
}...
would be more efficient.
That doesn't mean we shouldn't fix this PR.
