diff --git a/src/corelib/io/qurl.cpp b/src/corelib/io/qurl.cpp
index c71bb3afac849dee3c1c8dd7e3cc495a4bba700a..02e7b967ea58abffd15987cf9676515762a9d1e9 100644
--- a/src/corelib/io/qurl.cpp
+++ b/src/corelib/io/qurl.cpp
@@ -3731,7 +3731,7 @@ QString QUrl::errorString() const
         return QString();
 
     QString errorSource;
-    int errorPosition;
+    int errorPosition = 0;
     QUrlPrivate::ErrorCode errorCode = d->validityError(&errorSource, &errorPosition);
     if (errorCode == QUrlPrivate::NoError)
         return QString();