[Bug c++/109337] c++2a test concepts4.C passes when it should fail

[cjdb.ns at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109337

--- Comment #3 from Christopher Di Bella <cjdb.ns at gmail dot com> ---
This is apparently a Clang bug: the RHS of `R42c` isn't evaluated because of
short-circuiting. Apologies for the noise and thanks for helping me work
through it.