diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 178328ae198..0ba81bfa124 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -2782,7 +2782,7 @@ module ts {
             return <InterfaceTypeWithDeclaredMembers>type;
         }
 
-        function resolveClassOrInterfaceMembers(type: InterfaceType) {
+        function resolveClassOrInterfaceMembers(type: InterfaceType): void {
             let target = resolveDeclaredMembers(type);
             let members = target.symbol.members;
             let callSignatures = target.declaredCallSignatures;