How to handle the Xcode warning “no previous prototype for function…”?

Usually with warnings like this you can just define a function prototype at the top of your file, for instance:

BOOL FBIsDeviceIPad();

But in C a method with nothing between the braces, i.e. () actually implies there are an arbitrary number of parameters. Instead the definition should become (void) to denote no parameters:

BOOL FBIsDeviceIPad(void);

...

BOOL FBIsDeviceIPad(void) {
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 30200
  if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad) {
   return YES;
  }
#endif
  return NO;
}