diff --git a/src/corelib/io/qurl.cpp b/src/corelib/io/qurl.cpp
index 878e007fb0..a7650390f9 100644
--- a/src/corelib/io/qurl.cpp
+++ b/src/corelib/io/qurl.cpp
@@ -979,7 +979,7 @@ inline bool QUrlPrivate::setScheme(const QString &value, int len, bool doSetErro
 
     // validate it:
     int needsLowercasing = -1;
-    const ushort *p = reinterpret_cast<const ushort *>(value.constData());
+    const ushort *p = value.utf16();
     for (int i = 0; i < len; ++i) {
         if (p[i] >= 'a' && p[i] <= 'z')
             continue;