diff --git a/src/corelib/serialization/qjsondocument.h b/src/corelib/serialization/qjsondocument.h
index 758bbfd9dd0..fd3a3ac61d3 100644
--- a/src/corelib/serialization/qjsondocument.h
+++ b/src/corelib/serialization/qjsondocument.h
@@ -74,8 +74,8 @@ struct Q_CORE_EXPORT QJsonParseError
 
     QString    errorString() const;
 
-    int        offset;
-    ParseError error;
+    int        offset = -1;
+    ParseError error = NoError;
 };
 
 class QJsonDocumentPrivate;