diff --git a/Source/WebKit/Shared/UpdateInfo.h b/Source/WebKit/Shared/UpdateInfo.h
index dbb1be28348c..4494af0813a3 100644
--- a/Source/WebKit/Shared/UpdateInfo.h
+++ b/Source/WebKit/Shared/UpdateInfo.h
@@ -52,7 +52,7 @@ class UpdateInfo {
 
     // The size of the web view.
     WebCore::IntSize viewSize;
-    float deviceScaleFactor;
+    float deviceScaleFactor { 0 };
 
     // The rect and delta to be scrolled.
     WebCore::IntRect scrollRect;
@@ -65,7 +65,7 @@ class UpdateInfo {
     Vector<WebCore::IntRect> updateRects;
 
     // The page scale factor used to render this update.
-    float updateScaleFactor;
+    float updateScaleFactor { 0 };
 
     // The handle of the shareable bitmap containing the updates. Will be null if there are no updates.
     ShareableBitmap::Handle bitmapHandle;