2015-03-20 Andrew Sutton <andrew.n.sutton@gmail.com>

2015-03-20  Andrew Sutton  <andrew.n.sutton@gmail.com>

	Fix regression in variadic constraint processing.
	* gcc/cp/pt.c (tsubst_pack_expansion): Expose declaration.
	* gcc/cp/constraint.cc: Rename lift_constraints to
	lift_expression to better reflect what it does.
	(lift_pack_expansion): New. Handles naked pack expansions
	in a constriant.
	(check_pack_expansion): Special handling for checking naked
	pack expansions in constraints. This eventually be replaced
	by similar logic for fold expressions.
	(check_predicate_constraint): Handle pack expansions.
	* gcc/cp/cp-tree.h (tsubst_pack_expansion): Make this avaialble
	to constraints.cc.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/c++-concepts@221534 138bc75d-0d04-0410-961f-82ee72b054a4