diff --git a/lib/NormalModule.js b/lib/NormalModule.js
index b01d9d00b4b..b8165366efd 100644
--- a/lib/NormalModule.js
+++ b/lib/NormalModule.js
@@ -212,7 +212,7 @@ class NormalModule extends Module {
 			rootContext: options.context,
 			webpack: true,
 			sourceMap: !!this.useSourceMap,
-			mode: options.mode,
+			mode: options.mode || "production",
 			_module: this,
 			_compilation: compilation,
 			_compiler: compilation.compiler,