Why is the phrase: "undefined behavior means that the compiler can do whatever it wants" true?

Question

In particular, a link to: https://blogs.msdn.microsoft.com/oldnewthing/20140627-00/?p=633/

I am a new C ++ programmer, and I am currently studying undefined behavior, and this affects the program. I was specifically related to the aforementioned blog, which says that when undefined behavior occurs, anything can happen.

It mentions several times that the compiler can allow something to happen when undefined behavior occurs.

What exactly causes this event and why is this happening?

Answer 1

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