cvt.c (cp_convert_to_pointer): Remove force parameter.

cvt.c (cp_convert_to_pointer): Remove force parameter.

	gcc/cp/
	* cvt.c (cp_convert_to_pointer): Remove force parameter. Call
	convert_ptrmem for pointer to member conversions.
	(convert_to_pointer_force): Update cp_convert_to_pointer call.
	(ocp_convert): Update cp_convert_to_pointer call.
	* typeck.c (convert_ptrmem): Add conditional for null pointers to
	members.
	(build_static_cast_1): Check can_convert for conversions in either
	direction.
	(get_delta_difference_1): New function.
	(get_delta_difference): Refactor to call get_delta_difference_1.

	gcc/testsuite/
	g++.dg/conversion/ptrmem2.C: New test.
	g++.dg/conversion/ptrmem3.C: New test.
	g++.dg/conversion/ptrmem4.C: New test.
	g++.dg/conversion/ptrmem5.C: New test.
	g++.dg/conversion/ptrmem6.C: New test.
	g++.dg/conversion/ptrmem7.C: New test.
	g++.dg/conversion/ptrmem8.C: New test.

From-SVN: r127953