re PR debug/48853 (Wrong DWARF codegen when Pmode != ptr_mode)

re PR debug/48853 (Wrong DWARF codegen when Pmode != ptr_mode)

	PR debug/48853
	* dwarf2out.c (mem_loc_descriptor) <case SUBREG>: Pass mem_mode
	instead of mode as 3rd argument to recursive call.
	(mem_loc_descriptor) <case REG>: If POINTERS_EXTEND_UNSIGNED, don't
	emit DW_OP_GNU_regval_type if mode is Pmode and mem_mode is not
	VOIDmode.
	(mem_loc_descriptor) <case SYMBOL_REF>: If POINTERS_EXTEND_UNSIGNED,
	don't give up if mode is Pmode and mem_mode is not VOIDmode.
	(mem_loc_descriptor) <case CONST_INT>: If POINTERS_EXTEND_UNSIGNED,
	use int_loc_descriptor if mode is Pmode and mem_mode is not VOIDmode.

From-SVN: r173436