[Bug c++/115731] Coroutine lambda type is incomplete when selecting promise constructor

[arsen at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115731

--- Comment #3 from Arsen Arsenović <arsen at gcc dot gnu.org> ---
ah, no, never mind - it does.  per [expr.prim.lambda]#6,

  ... Otherwise, it is a non-static member function or member function
template, ...

so, yeah, we need to complete that type, likely