--- a/widget/windows/nsDeviceContextSpecWin.cpp
+++ b/widget/windows/nsDeviceContextSpecWin.cpp
@@ -91,18 +91,21 @@ struct AutoFreeGlobalPrinters
 {
   ~AutoFreeGlobalPrinters() {
     GlobalPrinters::GetInstance()->FreeGlobalPrinters();
   }
 };
 
 //----------------------------------------------------------------------------------
 nsDeviceContextSpecWin::nsDeviceContextSpecWin()
+  : mDevMode(nullptr)
+#ifdef MOZ_ENABLE_SKIA_PDF
+  , mPrintViaSkPDF(false)
+#endif
 {
-  mDevMode       = nullptr;
 }
 
 
 //----------------------------------------------------------------------------------
 
 NS_IMPL_ISUPPORTS(nsDeviceContextSpecWin, nsIDeviceContextSpec)
 
 nsDeviceContextSpecWin::~nsDeviceContextSpecWin()