No that's implementation-defined. Undefined means code that is logically incorrect, but too expensive for the compiler/runtime to check and handle (reject) it.

No that's implementation-defined. Undefined means code that is logically incorrect, but too expensive for the compiler/runtime to check and handle (reject) it. A simple example is array out of bounds access. It's too expensive to demand the compiler prevent it or guarantee to trigger some kind of signal at runtime. But if you are willing to pay the cost , you can use a language or compiler that is safer and promises to throw an exception or provides safe statically sizd arrays