Here reintroducing the same declarations into the global namespace via
using-declaration is useless but OK.  And a function and a function template
with the same parameters do not conflict.

gcc/cp/ChangeLog
2020-02-13  Jason Merrill  <jason@redhat.com>

	PR c++/93713
	* name-lookup.c (matching_fn_p): A function does not match a
	template.