diff --git a/lib/6to5/traversal/scope.js b/lib/6to5/traversal/scope.js
index e02a4165c0..73df51e376 100644
--- a/lib/6to5/traversal/scope.js
+++ b/lib/6to5/traversal/scope.js
@@ -249,8 +249,10 @@ var programReferenceVisitor = {
 
 var blockVariableVisitor = {
   enter: function (node, parent, scope, state) {
-    if (t.isBlockScoped(node)) {
-      state.register(node, null, "let");
+    if (t.isFunctionDeclaration(node)) {
+      state.register(node, false, "hoisted");
+    } else if (t.isBlockScoped(node)) {
+      state.register(node, false, "let");
     } else if (t.isScope(node)) {
       this.skip();
     }
@@ -272,9 +274,10 @@ Scope.prototype.crawl = function () {
 
   info = block._scopeInfo = {
     bindingKinds: {
-      "const": object(),
-      "var":   object(),
-      "let":   object()
+      "hoisted": object(),
+      "const":   object(),
+      "var":     object(),
+      "let":     object()
     },
 
     references: object(),