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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Using "extra" blocks to declare local variables (Was: switch/extension for see below strongly needed)
Date: Fri, 22 May 2026 23:44:02 -0700
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scott@slp53.sl.home (Scott Lurndal) writes:

> I often declare local variables within a compound statement
> introduced by a do/while/for/case construct.

I do this too, although I don't know if I would say often.
Probably closer to 50/50.  Also the same applies to if().

I commonly use the declaration syntax in for() statements to have
an iteration variable (or variables) local to the loop.

> In pre or post C99 code, I do not create compound statements
> willy-nilly just to hide a prior defined local variable with the
> same name (a maintenance nightmare, to be sure) or to locate the
> declaration closer to the use in a function.

I agree with both of these.  Very rarely I might introduce a
compound statement "out of the blue" not for either those reasons
but expressly to limit the scope of a variable in the midst of a
long and complicated function.  Especially because such cases are
rare, I like to flag them with double braces, something like

    {{  ULL carry = 0;
        for(...){
            ...    uses of carry
            ...    uses of carry
        }
        if(...)    uses of carry
        if(...)
    }}

(and yes, in case anyone is wondering, there are reasons why the
code in this case couldn't be abstracted into a sub-function).