https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65608 Bug 65608 depends on bug 41723, which changed state.
Bug 41723 Summary: [9/10 Regression] Error when using a qualified name to declare a nested template instantiation as a friend of the containing template https://gcc.gnu.org/bugzilla/show_bug.cgi?id=41723 What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution|--- |FIXED