diff --git a/src/libsyntax/tokenstream.rs b/src/libsyntax/tokenstream.rs
index db6832d64232..3d89e73d729f 100644
--- a/src/libsyntax/tokenstream.rs
+++ b/src/libsyntax/tokenstream.rs
@@ -202,9 +202,9 @@ impl From<TokenTree> for TreeAndJoint {
     }
 }
 
-impl<T: Into<TokenStream>> iter::FromIterator<T> for TokenStream {
-    fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> Self {
-        TokenStream::from_streams(iter.into_iter().map(Into::into).collect::<SmallVec<_>>())
+impl iter::FromIterator<TokenTree> for TokenStream {
+    fn from_iter<I: IntoIterator<Item = TokenTree>>(iter: I) -> Self {
+        TokenStream::new(iter.into_iter().map(Into::into).collect::<Vec<TreeAndJoint>>())
     }
 }