diff --git a/src/corelib/global/qglobal.h b/src/corelib/global/qglobal.h
index 0f3f0eda73..7d234c74b1 100644
--- a/src/corelib/global/qglobal.h
+++ b/src/corelib/global/qglobal.h
@@ -849,12 +849,6 @@ private:
 
 #endif // Q_OS_DARWIN
 
-/*
-   Data stream functions are provided by many classes (defined in qdatastream.h)
-*/
-
-class QDataStream;
-
 inline void qt_noop(void) {}
 
 /* These wrap try/catch so we can switch off exceptions later.