PR#3963: Graphics.wait_next_event in Win32 hangs if window closed

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@13740 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

Changes

@@ -48,6 +48,7 @@ Runtime system:
   point within the major heap.
 
 Bug fixes:
+- PR#3963: Graphics.wait_next_event in Win32 hangs if window closed
 - PR#4762: ?? is not used at all, but registered as a lexer token
 - PR#4887: input_char after close_in crashes ocaml (msvc runtime)
 - PR#4994: ocaml-mode doesn't work with xemacs21

otherlibs/win32graph/open.c

@@ -99,6 +99,7 @@ static LRESULT CALLBACK GraphicsWndProc(HWND hwnd,UINT msg,WPARAM wParam,LPARAM
                 // End application
         case WM_DESTROY:
                 ResetForClose(hwnd);
+		gr_check_open();
                 break;
         }
         caml_gr_handle_event(msg, wParam, lParam);