https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66834
--- Comment #7 from Andrew Sutton <andrew.n.sutton at gmail dot com> --- > I would expect a partial ordering to prefer the two-parameter overload in that > case. But yeah, it's a separate issue. The problem is that partial ordering doesn't apply to template parameters whose arguments can only be given explicitly. I got caught by this last year, and sent an email to core, and then (I think) Ville submitted a core issue or NB comment (I don't remember the details). Andrew
