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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: How to add ssize_t a by size_t b?
Date: Sat, 02 Oct 2021 14:47:50 -0700
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wij <wyniijj@gmail.com> writes:

> To simply the question of "a+b":
>
> ssize_t add(ssize_t a, size_t b) {
>  if(a+b would overflow) { set errno=ERANGE; }
>  a+=b;     // ?
>  return a;
> }
>
> Another example:
> ssize_t a=SSIZE_T_MIN;
> size_t b=SIZE_T_MAX;
> a+=b;      // Is this OK?  Or, How the addition is done correctly?

This problem is doable, but it is not trivial.  It makes a good
challenge problem for C experts.

Is it really important for you to find an answer?