Summary:
The patch contains the parsing and sema support for the `to` clause.
Patch based on the original post by Kelvin Li.
Reviewers: carlo.bertolli, hfinkel, kkwli0, arpith-jacob, ABataev
Subscribers: caomhin, cfe-commits
Differential Revision: http://reviews.llvm.org/D18597
llvm-svn: 270880