Hmm…let's try a simpler question, just so I can get a clearer picture of your opinion: what should the compiler do when I go off the end off an array? Add a check for the bounds? Not put a check and nondeterministically fail based on the the state of the program? How about when you overflow something? Or dereference a dangling pointer?

You seem to not be OK with allowing the compiler to trust the user to not do bad things–but you do trust them enough to out-optimize the compiler. Or am I getting you wrong?