c-typeck.c (enum impl_conv): Add ic_argpass_nonproto.

	* c-typeck.c (enum impl_conv): Add ic_argpass_nonproto.
	(convert_for_assignment): Handle ic_argpass_nonproto.  Add
	comments about its relevance to errors.
	(c_convert_parm_for_inlining): Use ic_argpass_nonproto.

testsuite:
	* gcc.dg/assign-warn-3.c: New test.

From-SVN: r88784