Question

I am compiling my program with a 3rd party library. That library contains an error callback if an error occurs internally. Inside that error callback I am throwing an exception and I have a unit test to verify that when I do something invalid that the exception is thrown. This all works beautifully in Windows, but when I test this in linux (fedora) I am getting an abort from an uncaught exception.

I tried wrapping my call directly with a try-catch block but no luck. ( Also, all my code is running within the google test framework which also normally catches exceptions ). The only thing that seems to catch the exception is if I wrap the throw statement in a try block directly within the error callback.

Does anyone have any idea why this would happen and if there is a way to catch the exception?

Answer 1

When you interface with third-party libraries you usually have to catch all exception on the border between your code and their code:

int yourCallback( params )
{
    try {
      doStuff( params );
      return Okay;
    } catch (...) {
      return Error;
    }
}

The reason is you can’t be sure that library is written in C++ or it uses the very same version of C++ runtime as your code uses.

Unless you’re completely sure that code can deal with your exceptions you can’t propagate exceptions to third-party code. The extreme example is COM where both your code and “other code” can be in whatever language and with whatever runtime and you are not allowed to let exceptions propagate through COM boundary.