diff --git a/src/compiler/scanner.ts b/src/compiler/scanner.ts
index 6326b0d8f80..3f7db7d2eb3 100644
--- a/src/compiler/scanner.ts
+++ b/src/compiler/scanner.ts
@@ -1483,7 +1483,7 @@ namespace ts {
 
         function scan(): SyntaxKind {
             startPos = pos;
-            tokenFlags = 0;
+            tokenFlags = TokenFlags.None;
             let asteriskSeen = false;
             while (true) {
                 tokenPos = pos;
@@ -2115,7 +2115,7 @@ namespace ts {
 
         function scanJsDocToken(): JSDocSyntaxKind {
             startPos = tokenPos = pos;
-            tokenFlags = 0;
+            tokenFlags = TokenFlags.None;
             if (pos >= end) {
                 return token = SyntaxKind.EndOfFileToken;
             }
@@ -2276,7 +2276,7 @@ namespace ts {
             tokenPos = textPos;
             token = SyntaxKind.Unknown;
             tokenValue = undefined!;
-            tokenFlags = 0;
+            tokenFlags = TokenFlags.None;
         }
 
         function setInJSDocType(inType: boolean) {