Rectangle is ambiguous on Windows

Rectangle is ambiguous on Windows

In file included from /usr/share/mingw-w64/include/windows.h:71:0,
                 from /home/ardour/win-stack-w32/include/pthread.h:198,
                 from /home/ardour/ardour-w32/libs/pbd/pbd/event_loop.h:29,
                 from /home/ardour/ardour-w32/libs/pbd/pbd/signals.h:42,
                 from /home/ardour/ardour-w32/libs/midi++2/midi++/parser.h:26,
                 from ../libs/surfaces/push2/mix.cc:30:

/usr/share/mingw-w64/include/wingdi.h:3049:67: note: candidates are: WINBOOL Rectangle(HDC, int, int, int, int)

In file included from ../libs/surfaces/push2/mix.cc:48:0:

/home/ardour/ardour-w32/libs/canvas/canvas/rectangle.h:30:48: note: class ArdourCanvas::Rectangle