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Newsgroups: comp.lang.ada
Date: Mon, 21 May 2018 17:39:52 -0700 (PDT)
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Subject: Re: Should exceeding the range of Integer wrap around a la C?
From: Jere <jhb.chat@gmail.com>
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Xref: reader02.eternal-september.org comp.lang.ada:52560
Date: 2018-05-21T17:39:52-07:00
List-Id: <comp.lang.ada>

On Monday, May 21, 2018 at 3:11:45 PM UTC-4, Paul Rubin wrote:
> > Should exceeding the range of Integer wrap around a la C?
> SNIPPED..
> 
> In C, unsigned integer overflow is undefined behaviour, like a subscript
> overflow.  Wraparound is one common result because of how machine
> arithmetic works, but it is not guaranteed.  The program could instead
> crash, or delete your files, or anything else.  See here:
> 
> http://blog.llvm.org/2011/05/what-every-c-programmer-should-know.html

Just wanted to point this out because I think you have a typo, but 
overflow for unsigned integers is completely defined in the C standard.
It is considered wraparound logic [1].  Signed integer overflow is 
undefined behavior however.

[1] Section 6.2.5/9 of the C11 standard