PR c++/34691
	* name-lookup.c	(merge_functions): Keep multiple extern "C" functions.
	* call.c (joust): Complain about mismatched default arguments
	in extern "C" functions.
	* class.c (resolve_address_of_overloaded_function): Handle multiple
	extern "C" functions.
	* pt.c (resolve_overloaded_unification): Likewise.

From-SVN: r145709