diff --git a/packages/@ngtools/webpack/src/type_checker.ts b/packages/@ngtools/webpack/src/type_checker.ts
index 92f2ef529dc0..ef20fb4f2af4 100644
--- a/packages/@ngtools/webpack/src/type_checker.ts
+++ b/packages/@ngtools/webpack/src/type_checker.ts
@@ -97,7 +97,6 @@ class TypeChecker {
       options: this._angularCompilerOptions,
       tsHost: compilerHost
     }) as CompilerHost & WebpackCompilerHost;
-    this._tsFilenames = [];
     timeEnd('TypeChecker.constructor');
   }