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From: David Brown <david.brown@hesbynett.no>
Newsgroups: comp.lang.c
Subject: Re: integer divided by zero
Date: Wed, 30 Apr 2025 13:35:09 +0200
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On 30/04/2025 12:41, Rosario19 wrote:
> On Fri, 25 Apr 2025 12:05:13 -0700, Keith Thompson wrote:
> 
>> Thiago Adams writes:
>>> Does anyone know of any platform where integer division by zero
>>> returns a number, or in other words, where it's not treated as an
>>> error? I'm asking because division by zero is undefined behaviour, but
>>> I think division by a constant zero should be a constraint instead.
>>
>> Division by a constant zero is a constraint violation in a context that
>> requires a constant expression.
>>
>> I wrote this quick and dirty program:
>>
>> #include <stdio.h>
>> #include <time.h>
>> int main(void) {
>>     int one = time(NULL) / 1000000000;
>>     int zero = one - 1;
>>     int ratio = one / zero;
>>     printf("%d\n", ratio);
> 
> in math
> 1/0 has to be +infinite ( for approximation +INT_MAX for C?)

In common mathematics, 1 / 0 is undefined - just like in C.  If you 
extend the set of real numbers to include some kind of infinity ∞ , you 
immediately lose many other useful properties of the set.  INT_MAX is 
not a good approximation - there is no int value that makes sense for 
the result of 1 / 0.