Loren J. Rittle <ljrittle@acm.org>

	* include/bits/basic_string.h
	(basic_string::_Rep::__default_excess, _S_excess_slop):
	Unused, remove.
	* include/bits/basic_string.tcc: Remove dead code.
	* include/bits/c++config: Remove comment.

Co-Authored-By: Loren J. Rittle <ljrittle@acm.org>

From-SVN: r47425