If -no-webkit option is passed to configure, the qmake still runs on WebKit files

If -no-webkit option is set, the qmake still runs on files it shouldn't.

Configure script ./configure -prefix . -no-webkit

In the configure log:
WARNING: Failure to find: generated/AuthenticationManagerMessageReceiver.cpp
WARNING: Failure to find: generated/DownloadProxyMessageReceiver.cpp
WARNING: Failure to find: generated/DrawingAreaMessageReceiver.cpp
WARNING: Failure to find: generated/DrawingAreaProxyMessageReceiver.cpp
WARNING: Failure to find: generated/NPObjectMessageReceiverMessageReceiver.cpp
WARNING: Failure to find: generated/PluginControllerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/PluginProcessMessageReceiver.cpp
WARNING: Failure to find: generated/PluginProcessProxyMessageReceiver.cpp
WARNING: Failure to find: generated/PluginProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebApplicationCacheManagerMessageReceiver.cpp
WARNING: Failure to find: generated/WebApplicationCacheManagerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebContextMessageReceiver.cpp
WARNING: Failure to find: generated/WebCookieManagerMessageReceiver.cpp
WARNING: Failure to find: generated/WebCookieManagerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebDatabaseManagerMessageReceiver.cpp
WARNING: Failure to find: generated/WebDatabaseManagerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebFullScreenManagerMessageReceiver.cpp
WARNING: Failure to find: generated/WebFullScreenManagerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebGeolocationManagerMessageReceiver.cpp
WARNING: Failure to find: generated/WebGeolocationManagerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebIconDatabaseMessageReceiver.cpp
WARNING: Failure to find: generated/WebIconDatabaseProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebInspectorMessageReceiver.cpp
WARNING: Failure to find: generated/WebInspectorProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebKeyValueStorageManagerMessageReceiver.cpp
WARNING: Failure to find: generated/WebKeyValueStorageManagerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebMediaCacheManagerMessageReceiver.cpp
WARNING: Failure to find: generated/WebMediaCacheManagerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebPageMessageReceiver.cpp
WARNING: Failure to find: generated/WebPageProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebProcessConnectionMessageReceiver.cpp
WARNING: Failure to find: generated/WebProcessMessageReceiver.cpp
WARNING: Failure to find: generated/WebProcessProxyMessageReceiver.cpp
WARNING: Failure to find: generated/WebResourceCacheManagerMessageReceiver.cpp
WARNING: Failure to find: generated/WebResourceCacheManagerProxyMessageReceiver.cpp
WARNING: Failure to find: generated/AuthenticationManagerMessages.h
WARNING: Failure to find: generated/DownloadProxyMessages.h
WARNING: Failure to find: generated/NPObjectMessageReceiverMessages.h
WARNING: Failure to find: generated/PluginControllerProxyMessages.h
WARNING: Failure to find: generated/PluginProcessMessages.h
WARNING: Failure to find: generated/PluginProcessProxyMessages.h
WARNING: Failure to find: generated/PluginProxyMessages.h
WARNING: Failure to find: generated/WebApplicationCacheManagerMessages.h
WARNING: Failure to find: generated/WebApplicationCacheManagerProxyMessages.h
WARNING: Failure to find: generated/WebContextMessages.h
WARNING: Failure to find: generated/WebCookieManagerMessages.h
WARNING: Failure to find: generated/WebCookieManagerProxyMessages.h
WARNING: Failure to find: generated/WebDatabaseManagerMessages.h
WARNING: Failure to find: generated/WebDatabaseManagerProxyMessages.h
WARNING: Failure to find: generated/WebFullScreenManagerMessages.h
WARNING: Failure to find: generated/WebFullScreenManagerProxyMessages.h
WARNING: Failure to find: generated/WebGeolocationManagerMessages.h
WARNING: Failure to find: generated/WebGeolocationManagerProxyMessages.h
WARNING: Failure to find: generated/WebIconDatabaseMessages.h
WARNING: Failure to find: generated/WebIconDatabaseProxyMessages.h
WARNING: Failure to find: generated/WebInspectorMessages.h
WARNING: Failure to find: generated/WebInspectorProxyMessages.h
WARNING: Failure to find: generated/WebKeyValueStorageManagerMessages.h
WARNING: Failure to find: generated/WebKeyValueStorageManagerProxyMessages.h
WARNING: Failure to find: generated/WebMediaCacheManagerMessages.h
WARNING: Failure to find: generated/WebMediaCacheManagerProxyMessages.h
WARNING: Failure to find: generated/WebPageMessages.h
WARNING: Failure to find: generated/WebPageProxyMessages.h
WARNING: Failure to find: generated/WebProcessConnectionMessages.h
WARNING: Failure to find: generated/WebProcessMessages.h
WARNING: Failure to find: generated/WebProcessProxyMessages.h
WARNING: Failure to find: generated/WebResourceCacheManagerMessages.h
WARNING: Failure to find: generated/WebResourceCacheManagerProxyMessages.h
for /home/user/Qt_versions/qt-4.8.1_test/src/3rdparty/webkit/Source/WebKit2/DerivedSources.pro
WARNING: DESTDIR: Cannot access directory '/include/WebCore'