Add syntax support for attributes on expressions and all syntax

nodes in statement position.

Extended #[cfg] folder to allow removal of statements, and
of expressions in optional positions like expression lists and trailing
block expressions.

Extended lint checker to recognize lint levels on expressions and
locals.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/libsyntax/visit.rs b/src/libsyntax/visit.rs
index 5d4a462e844..2d97e2680d7 100644
--- a/src/libsyntax/visit.rs
+++ b/src/libsyntax/visit.rs
@@ -628,7 +628,12 @@ pub fn walk_stmt<'v, V: Visitor<'v>>(visitor: &mut V, statement: &'v Stmt) {
         StmtExpr(ref expression, _) | StmtSemi(ref expression, _) => {
             visitor.visit_expr(expression)
         }
-        StmtMac(ref mac, _) => visitor.visit_mac(mac),
+        StmtMac(ref mac, _, ref attrs) => {
+            visitor.visit_mac(mac);
+            for attr in attrs.as_attrs() {
+                visitor.visit_attribute(attr);
+            }
+        }
     }
 }