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From: Rainer Weikusat <rweikusat@talktalk.net>
Newsgroups: comp.unix.programmer,comp.lang.c
Subject: Re: Odd compiler behaviour?
Date: Tue, 01 Mar 2016 21:20:45 +0000
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Richard Kettlewell <rjk@greenend.org.uk> writes:
> Barry Margolin <barmar@alum.mit.edu> writes:

[...]

>> Wow, you totally misunderstand the point of declaring out-of-bounds 
>> access to be UB.
>> 
>> The compiler can still generate the first code, and in fact that's
>> what I'd expect most compilers to do.  It doesn't have to check
>> bounds,
>
> “Do anything you like” - in other words, undefined behavior - includes
> the first line, but not exclusively.

"Nobody's asked to do anything specific" ('undefined behaviour') is
something rather different fromj "do anything you like".