https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78771
--- Comment #2 from Nathan Sidwell <nathan at gcc dot gnu.org> --- Created attachment 40345 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40345&action=edit simpler testcase the deletedness of the template ctor is a red herring. Also the templatedness of the base class. This testcase ices in the same way -- we end up looking for a clone during the middle of instantiating the non-clone origin.