Code freezes on if statement

This if statement:

if (ButtonPress)
{
    Mix_PlayChannel(1, ButtonPress, 0);
}

works like this:

if (SelectButton)
{
    if (Press_Enter)
    {
        ButtonPress = true;
    }
}

However when the code reaches the if statement in question, the program entirely freezes and the code stops running. It might be worth noting that I'm using Visual Studio 2015 and SDL, also having made sure I've initialized everything beforehand. So why does the code freeze on this if statement?