Build failure in Qt 5.9 head from git

In file included from qcocoaapplicationdelegate.mm:75:
./qcocoaapplicationdelegate.h:101:17: error: implicit instantiation of undefined template 'QList<QWindow *>'
{{ QWindowList hiddenWindows;}}
{{ ^}}
../../../../include/QtGui/../../src/gui/kernel/qwindowdefs.h:83:28: note: template is declared here
template<typename T> class QList;
{{ ^}}
In file included from qcocoaapplication.mm:77:
./qcocoaapplicationdelegate.h:101:17: error: implicit instantiation of undefined template 'QList<QWindow *>'
{{ QWindowList hiddenWindows;}}
{{ ^}}
../../../../include/QtGui/../../src/gui/kernel/qwindowdefs.h:83:28: note: template is declared here
template<typename T> class QList;
{{ ^}}
1 error generated.
make[4]: *** [.obj/qcocoaapplication.o] Error 1