[Bug c++/68929] GCC hangs in nested template instantiations even after static_assert fails.

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68929

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Probably related to PR c++/96286, because if we stopped trying to compile a
class after a failed static_assert then we wouldn't keep recursing in Eric's
example here.