Fix mingw32 building errors.

sys/windows/stubs.c

@@ -10,7 +10,6 @@
 #error You cannot compile this with both GUISTUB and TTYSTUB defined.
 #endif
 
-int GUILaunched;
 struct window_procs mswin_procs = { "-guistubs" };
 
 #ifdef QT_GRAPHICS
@@ -60,7 +59,6 @@ main(int argc, char *argv[])
 
 HANDLE hConIn;
 HANDLE hConOut;
-int GUILaunched;
 struct window_procs tty_procs = { "-ttystubs" };
 #ifdef CURSES_GRAPHICS
 char erase_char, kill_char;

sys/windows/windsys.c

@@ -45,7 +45,7 @@ boolean win32_cursorblink;
 HANDLE ffhandle = (HANDLE) 0;
 WIN32_FIND_DATA ffd;
 extern int GUILaunched;
-boolean getreturn_enabled;
+extern boolean getreturn_enabled;
 int redirect_stdout;
 
 typedef HWND(WINAPI *GETCONSOLEWINDOW)();