[Bug c++/84893] Rejects a valid code with variadic function template taking a function pointer

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84893

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
We have a number of very similar bugs related to deducing function types from
function pointers.