[Bug c++/67762] [C++1z] 'not a constant expression" errors only with -fsanitize=undefined

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67762

--- Comment #2 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
The compile-time error goes away when adding
-fno-sanitize=null,returns-nonnull-attribute,nonnull-attribute to the
command-line options.