https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100894
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
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Target Milestone|--- |10.4
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
For the next time I can't figure out how this works ...
COMMON-REF(A&, B&&) is COMMON-REF(B&&, A&) which is COMMON-REF(const B&, A&)
which is COND-RES(const B&, const A&) if that is a reference type, ill-formed
otherwise. Since the COND-RES type is just B, it's ill-formed.
That means that common_reference_t<A&, B&&> uses the third bullet, so it's
COND-RES(A&, B&&) which is B.
