c++ - app -> extension crash on callback invocation -

i have marmalade extension , sample app passes c-callback function extension, happens whenever extension tries call function, crashes mysterious message:

exception type: exc_bad_access (sigsegv) exception codes: kern_invalid_address @ 0x00000008 crashed thread: 0

although, before call function print it's address , it's different , seems valid. marmalade restrictions or doing wrong?

p.s: worth notice compile marmalade extension clang (not gcc) , works fine, callbacks... although used default marmalade gcc before , had same issue.

sample app:

class cdemoapp { public:     static cdemoapp* getinstance() {         static cdemoapp instance;         return &instance;     }      void setup()     {         app = createapp();         window = createwindow();         app->addwindow(window);         view = createview("canvas");          button = createbutton();          button->seteventhandler("click", (void*)null, cdemoapp::onbutton1click);          view->addchild(button);         window->setchild(view);          app->showwindow(window);     }      void run() {         app->run();     }      static void onsdkinit(const char* err, void* context) {         printf("done.\n");     }      static bool onbutton1click(void* data, cbutton* button) {         if(!s3emyextdidinitialize()) {             // crash happens here.             // extension doesn't perform ops, calls callback dummy arguments             s3emyextdoinitialize(app_id, app_secret, cdemoapp::onsdkinit, null);         }          return true;     }  private:     cdemoapp() {};  private:     cappptr app;     cwindowptr window;     cviewptr view;     cbuttonptr button; };  // main entry point application int main() {     if(!s3emyextavailable())     {         s3edebugerrorshow(s3e_message_continue, "my extension not found");         return 0;     }      cdemoapp::getinstance()->setup();     cdemoapp::getinstance()->run();      return 0; } 

the function s3emyextdoinitialize exposed extension looks that:

typedef void (*my_callback)(const char* error, void* context); void s3emyextdoinitialize_platform(const char* appid, const char* appsecret, my_callback callback, void* context) {      callback(null, null);  } 

well, apparently there's no way pass function pointer app extension directly, marmalade offers own callbacks system should utilized things work.