[Bug c++/109277] [13 Regression] type_traits:1417:30: error: invalid use of incomplete type ‘class v8::internal::WasmArray’

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109277

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Yes, looks undefined at first glance. We don't have to diagnose bad uses of
type traits (but we don't have to ignore them either, which means both gcc 12
and gcc 13 are correct).

The question is whether the trait instantiation is supposed to happen here, or
if it should be ok to name the incomplete type as long as its not used before
it's complete.