re PR c++/79962 (ICE nonnull_check_p on a function template with a type-dependent attribute nonnull)

	PR c++/79962
	PR c++/79984
	* c-attribs.c (handle_nonnull_attribute): Save the result of default
	conversion to the attribute list.

	* c-c++-common/nonnull-3.c: New test.
	* g++.dg/warn/Wnonnull3.C: New test.

From-SVN: r246016