US100 13.01 p4.1 Reference types should not have strong structural equality

[wg21bot]

Reference types (of which there are no glvalues) seem to vacuously have strong structural equality, which would allow an rvalue reference (which is a literal type) as a template parameter.

Proposed change:
Explicitly exclude all reference types from strong structural equality.

[jensmaurer]

CWG in Belfast: Accepted with modification. See paper P1907R1.