https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79381
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |accepts-invalid
Status|UNCONFIRMED |RESOLVED
Resolution|--- |INVALID
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I think the program is valid and GCC is right to accept it.
The constraint checking doesn't need to check that the entire instantiation of
DeriveFrom<void(*)()> is valid, so doesn't check the base classes.
It also compiles if DeriveFrom is incomplete:
template<class> struct DeriveFrom;
All the constraint checks is that DeriveFrom<T> is a type, which doesn't
require it to be complete or able to be instantiated.
