Behavior of overflowing integers. [particularly C]

Is the behavior of overflowing integers (of any size) standard across platforms? What exactly happens if I overfill or oversubtract unsigned integers? I'm asking this because I'm writing an emulator which may encounter arithmetic situations where this may occur.

Xyne wrote:
kazuo wrote:ISO C99 says that overflow are "undefined behavior" i.e. anything can happen and its ok. Wrap around? OK Program abort? OK, Pregnant cat? OK.
Good thing it only applies to cats and not humans, otherwise bad programmers all over the world would have to have this conversation:
Girl: Are you sure it will be ok?
Guy: Don't worry, I know what I'm doing... my integers never overflow. Just relax and trust me.
Lol!! Hahaha
@Anikom15 You can get the needed info on google, this is a very common topic (its is a FAQ at comp.lang.c FAQ). For example look at http://www.fefe.de/intof.html
EDIT, now re-reading your last message looks like you question now is in a more general sense. You can look at something like http://en.wikipedia.org/wiki/Arbitrary- … arithmetic , but the final solution (bignum, or safe overflow, using bigger types) is per case basis. For example, if you know that you are limited to 64bit sizes you can use it (simple use a 64 bit type) if the needed type is not available you can create then (using for example two smaller types), as I said all depends of the user case.
Last edited by kazuo (2010-06-14 00:40:10)

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[Re: Creating Rpt Conmgr Cache File In Temp folder while opening report from app|Re: Creating Rpt Conmgr Cache File In Temp folder while opening report from app]
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- Kirti
Edited by: KirtiRK on Oct 12, 2010 5:45 PM

Ludek,
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Good Server   ~10s
Bad Server     ~10s
Subsequent Loads
Good Server < 1s
Bad Server    < 1s
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The modified dates are somewhat different for many of the modules/assemblies, but most of them match up exactly with file size and version. I will dig in here as well to see if I can find any notable differences.
Environment Factor
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Behavior of overflowing integers. [particularly C]

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