[Bug c++/125563] GCC accepts a default argument that invokes a deleted constructor in the inner class of a class template

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125563

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Yes, the constructor is never instantiated, and the default argument is not
used. The compiler is not required to diagnose this.