2018-08-21 François Dumont <fdumont@gcc.gnu.org>

2018-08-21  François Dumont  <fdumont@gcc.gnu.org>

	P0646R1 Improving the Return Value of Erase-Like Algorithms I
	* include/debug/forward_list (forward_list::__remove_return_type):
	Define typedef as size_type or void, according to __cplusplus value.
	(_GLIBCXX_FWDLIST_REMOVE_RETURN_TYPE_TAG): Define macro as abi-tag or
	empty, according to __cplusplus value.
	(_GLIBCXX20_ONLY): Define macro.
	(forward_list::remove, forward_list::unique): Use typedef and macro
	to change return type and add abi-tag for C++2a. Return number of
	removed elements for C++2a.
	(forward_list::remove_if<Pred>, forward_list::unique<BinPred>): Use
	typedef to change return type for C++2a. Return number of removed
	elements for C++2a.
	* include/debug/list (list::__remove_return_type): Define typedef as
	size_type or void, according to __cplusplus value.
	(_GLIBCXX_LIST_REMOVE_RETURN_TYPE_TAG): Define macro as abi-tag or
	empty, according to __cplusplus value.
	(_GLIBCXX20_ONLY): Define macro.
	(list::remove, list::unique): Use typedef and macro to change return
	type and add abi-tag for C++2a. Return number of removed elements for
	C++2a.
	(list::remove_if<Predicate>, list::unique<BinaryPredicate>): Use typedef
	to change return type for C++2a. Return number of removed elements for
	C++2a.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@263752 138bc75d-0d04-0410-961f-82ee72b054a4