diff --git a/src/tools/clangbackend/clangbackendmain.cpp b/src/tools/clangbackend/clangbackendmain.cpp
index 571c4ebe3bc..56a4c9f8149 100644
--- a/src/tools/clangbackend/clangbackendmain.cpp
+++ b/src/tools/clangbackend/clangbackendmain.cpp
@@ -57,7 +57,7 @@ QString processArguments(QCoreApplication &application)
 }
 
 #ifdef Q_OS_WIN
-extern "C" void __stdcall OutputDebugStringW(const wchar_t* msg);
+#include <windows.h>
 static void messageOutput(QtMsgType type, const QMessageLogContext &/*context*/,
                           const QString &msg)
 {