borrowck changes: some copies, some removed mut annotations, some dvec

src/libsyntax/print/pprust.rs

@@ -1703,7 +1703,7 @@ fn print_comment(s: ps, cmnt: comments::cmnt) {
         // We need to do at least one, possibly two hardbreaks.
         let is_semi =
             alt s.s.last_token() {
-              pp::STRING(s, _) { s == ";" }
+              pp::STRING(s, _) { *s == ";" }
               _ { false }
             };
         if is_semi || is_begin(s) || is_end(s) { hardbreak(s.s); }