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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: size_t best practice
Date: Thu, 22 Aug 2024 01:38:24 -0700
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Andrey Tarasevich <andreytarasevich@hotmail.com> writes:

> On 08/20/24 6:55 AM, Andrey Tarasevich wrote:
>
>> On 08/20/24 6:53 AM, Andrey Tarasevich wrote:
>>
>>> For example, iteration all the way to 0 can be idiomatically
>>> implemented as
>>>
>>>  for (some_unsigned_type i = size; (some_unsigned_type) i != -1; --i)
>>>  ...
>>
>> Sorry, a typo.  Was meant to be
>>
>>   for (some_unsigned_type i = size; i != (some_unsigned_type) -1; --i)
>>   ...
>
> Of, crap.  One more time
>
>   for (some_unsigned_type i = size - 1;
>        i != (some_unsigned_type) -1;
>        --i)
>     ...
>
> Should be good now :)

To me the redundant cast is a red flag.  A cleaner alternative:

   for( some_unsigned_type i = size;  i > 0 && i--;  ){
      ...
   }

Produces identical code to the above at -O1 (both gcc and clang).