[int_19h]

I wouldn't like warnings for these things. I'd like them all to trap in a well-defined (but non-recoverable) way if UB actually gets triggered. And I'd like this to be the default behavior, even in release builds. Safety should never be opt-in.

[nlewycky]

I can offer you -fsanitize=undefined -fsanitize-trap=undefined, which you'd need to put in your configuration for release builds, presumably you have other flags in your build system (like -O2) already.

It's possible that a program terminating based on attacker influenced values could be used as a channel to leak confidential data to the attacker, so I'd suggest that developers decide whether to use this on a case-by-case basis. (Maybe it should default to on, but we'd need user education so people who are building sensitive systems know they need to turn it off.)