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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c++
Subject: Re: Is this really necessary
Date: Tue, 10 Aug 2021 06:11:33 -0700
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Vir Campestris <vir.campestris@invalid.invalid> writes:

[..stuff about 64 bit systems removed..]

> What bothers me about ptr_diff_t is the size.  The difference between
> two 32-bit pointers is plus or minus 4GB.  Which needs a 33 bit value
> :(
>
> As it happens it's never been a practical problem as I've never had a
> 32 bit system with more than 2GB RAM,

It isn't necessary for there to be more than 2GB of RAM for
problems with ptrdiff_t to manifest (in 32-bit linux).  A call to
malloc() will gladly return a memory area larger than all of RAM
if there is swap space to hold it.