https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89367
--- Comment #6 from Frank Secilia <frank.secilia at gmail dot com> --- I can't find anything in the standard under `constant expressions` or `converted constant expressions` that explicitly allows non-null pointer-to-member-functions in constexpr contexts, but I also can't find anything since N4268 that explicitly forbids them. It looks like icc and msvc accept this as well. Here are some godbolt results for x86_64: clang 7.0 - https://godbolt.org/z/sg-da1 icc 19.0.1 - https://godbolt.org/z/X8eqy1 msvc 19.16 - https://godbolt.org/z/5gbv83
