[zzalpha]

Uhh... The question was "what's an example of undefined behaviour". I gave one, specifically of an example that could realistically break by relying on undefined behaviour.

That's it. Simple education.

In the context of this post I think that's a good thing because not everyone will understand the topic.

You, however, seen to have read some sort of agenda in the question, which I find a little baffling...

[copsarebastards]

You're right; I'm sorry for misreading your intention. I've edited my post so it's not as directed at you.

[Dylan16807]

But that's not "undefined behavior" either. The post misleads people.

Certain things are unspecified. It can call in any order for example.

Other things are undefined. If you do them your program is no longer valid at all, and can crash or corrupt.

[nitrogen]

To reiterate/emphasize this point: "undefined", "unspecified", and a few other related terms are Things in C. They have specific, non-interchangeable, well-defined meanings in the C specifications.