https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67139
Eric Niebler <eric.niebler at gmail dot com> changed:
What |Removed |Added
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Summary|[concepts] ICE on checking |[concepts] ICE on checking
|concepts with void |concepts with void with
| |variable template
--- Comment #3 from Eric Niebler <eric.niebler at gmail dot com> ---
The problem goes away when _v<T> is replaced with the equivalent T::type::value
in concept IsTrue_, so that seems to be the smoking gun.
