[Bug c++/105672] Print note when unable to convert between types with the same name but different scopes

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105672

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #0)
> <error loc>:<col>: note: tuple and std::tuple are not the same type

And just to be clear, it was very intentional that this suggestion *doesn't*
show the template argument lists. That's just clutter in this context (and
those arg lists are already shown in the "error:" line). The template arg lists
are irrelevant here, *no* argument list is going to make them the same type, so
showing it doesn't help.

What matters here is the nested-name-specifier and the name after it.