https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66042
David Stone <david at doublewise dot net> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |INVALID --- Comment #2 from David Stone <david at doublewise dot net> --- It looks like gcc behaves correctly, which can be seen by adding the line auto x = compiles(0); I wasn't actually instantiating the template, just looking at its return type. This can be closed; sorry for the noise.