QPaintDevice: Must construct a QApplication before a QPaintDevice

编译移植ffmpeg-2.3.2, SDL-1.2.15, qtopia-2.2.0到4412开发板，好不容易都编译通过了，运行时报错：QPaintDevice: Must construct a QApplication before a QPaintDevice，网上帖子说是qwt.pro的release/debug问题，可是FriendlyARM提供qtopia-2.2.0里并没有什么qwt，或者网贴说的PC上VS编译环境的。本人Qt不懂，有没有高手遇到这个问题，请赐教！谢谢

问题貌似出在SDL，

    SDL_Init()
    \|/
    SDL_InitSubSystem()
    \|/
    SDL_VideoInit()
    \|/
    (1) video = bootstrap->create(index);

        static VideoBootStrap *bootstrap[] = {
            ...
        #if SDL_VIDEO_DRIVER_QTOPIA
            &Qtopia_bootstrap,
        #endif
            ...
        };

        VideoBootStrap Qtopia_bootstrap = {
            "qtopia", "Qtopia / QPE graphics",
            QT_Available, QT_CreateDevice
        };
        \|/
        QT_CreateDevice()
        {
            device->VideoInit = QT_VideoInit;
        }

    (2) if ( video->VideoInit(video, &vformat) < 0 ) {
        \|/
        QT_VideoInit()
        {
            ((QPEApplication*)qApp)->showMainWidget(SDL_Win);
        }
qApp找不到在哪里创建new？貌似应该在SDL_InitQPEApp()，可是，SDL_InitQPEApp()没有被调用

[root@fc9 SDL-1.2.15]# vim src/video/qtopia/SDL_sysvideo.cc
+    #include "SDL_QPEApp.h"            注意：不要放在extern "C"{} 里，否则链接时会报错SDL_InitQPEApp()找不到相应的二进制码

extern "C" {
    ...
}

int QT_VideoInit(_THIS, SDL_PixelFormat *vformat)
{
+    SDL_InitQPEApp();
    QSize desktop_size = qApp->desktop()->size();

void QT_VideoQuit(_THIS)
{
    QT_GrabInput(_this, SDL_GRAB_OFF);
+    SDL_QuitQPEApp();

[root@fc9 SDL-1.2.15]# vim src/video/qtopia/SDL_QPEApp.cc
-    char *argv[] = { { "SDLApp" } };
+    char *argv[] = { (char *){ "SDLApp" } };
    app = new QPEApplication(argc, argv);
+    qApp = app;

[root@fc9 SDL-1.2.15]# vim src/video/qtopia/SDL_QWin.cc
-    my_painter->end();
+    //my_painter->end();
    delete my_painter;