[Bug ada/124228] comparison of protected procedure to null as itype causes crash

[liam at liampwll dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124228

--- Comment #1 from Liam Powell <liam at liampwll dot com> ---
This also happens when comparing them to each other (X'Access = X'Access).