gcc/
	* tree.def (VOID_CST): New.
	* tree-core.h (TI_VOID): New.
	* tree.h (void_node): New.
	* tree.c (tree_node_structure_for_code, tree_code_size)
	(iterative_hash_expr): Handle VOID_CST.
	(build_common_tree_nodes): Initialize void_node.

gcc/c-family/
	* c-common.h (CTI_VOID_ZERO, void_zero_node): Delete.
	* c-common.c (c_common_nodes_and_builtins): Don't initialize
	void_zero_node.
	* c-pretty-print.c (pp_c_void_constant): New function.
	(c_pretty_printer::constant, c_pretty_printer::primary_expression)
	(c_pretty_printer::expression): Handle VOID_CST.
	* cilk.c (extract_free_variables): Likewise.
	* c-ubsan.c (ubsan_instrument_division, ubsan_instrument_shift)
	(ubsan_instrument_vla): Use void_node instead of void_zero_node.

gcc/c/
	* c-array-notation.c (expand_array_notations): Use void_node
	instead of void_zero_node.

gcc/cp/
	* cvt.c (convert_to_void): Use void_node instead of void_zero_node.
	* cp-array-notation.c (replace_invariant_exprs): Likewise.
	(expand_array_notation): Handle VOID_CST.
	* error.c (dump_expr): Likewise.
	* cxx-pretty-print.c (cxx_pretty_printer::primary_expression)
	(cxx_pretty_printer::expression): Likewise.
	(pp_cxx_new_expression): Use void_node instead of void_zero_node.
	* decl.c (register_dtor_fn): Likewise.
	* init.c (build_raw_new_expr, build_new_1, build_vec_init)
	(build_delete, push_base_cleanups): Likewise.
	* mangle.c (write_expression): Likewise.
	* semantics.c (finish_break_stmt, empty_expr_stmt_p): Likewise.
	* pt.c (tsubst_decl, tsubst_copy_and_build): Likewise.
	(tsubst, tsubst_copy, build_non_dependent_expr): Handle VOID_CST.
	* tree.c (cp_tree_equal): Likewise.
	(build_dummy_object, is_dummy_object, stabilize_expr): Use void_node
	instead of void_zero_node.
	* typeck.c (check_return_expr): Likewise.
	* typeck2.c (build_functional_cast): Likewise.

From-SVN: r210692