* cp-tree.h (enum cp_tree_index): Add CPTI_PFN_VFLAG_IDENTIFIER.
	(pfn_vflag_identifier): Define.
	Update comment about layout of pointer functions.
	(build_ptrmemfunc1): Update prototype.
	(expand_ptrmemfunc_cst): Update prototype.
	* decl.c (initialize_predefined_identifiers): Initialize
	pfn_vflag_identifier.
	(build_ptrmemfunc_type): When FUNCTION_BOUNDARY < 16, add
	an extra field to the type.
	* expr.c (cplus_expand_constant): Pass 'flag' between
	expand_ptrmemfunc_cst and build_ptrmemfunc1.
	* typeck.c (get_member_function_from_ptrfunc): When
	FUNCTION_BOUNDARY < 16, look at additional field to determine
	if a pointer-to-member is a real pointer or a vtable offset.
	(build_ptrmemfunc1): Add new parameter to contain extra field.
	(build_ptrmemfunc): Pass the extra field around.
	(expand_ptrmemfunc_cst): Add new parameter to return extra field.
	(pfn_from_ptrmemfunc): Ignore the extra field.

From-SVN: r41824