Re: Concatenated if and preprocessor

From	Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups	comp.lang.c
Subject	Re: Concatenated if and preprocessor
Date	2025-03-14 14:10 -0700
Organization	None to speak of
Message-ID	<87zfhniaij.fsf@nosuchdomain.example.com> (permalink)
References	<vquuhg$34o8d$2@dont-email.me> <vr15ti$rtjs$1@dont-email.me> <86frjfsgtb.fsf@linuxsc.com> <vr1rni$1q6m7$1@dont-email.me> <86bju3s5vp.fsf@linuxsc.com>

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Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
> Richard Harnden <richard.nospam@gmail.invalid> writes:
>> On 14/03/2025 16:44, Tim Rentsch wrote:
>>>    for(  int just_once = 1;  just_once;  just_once = 0  ){
>>
>> Any reason not to say ...
>>
>> do {
>>     ...
>> } while (0);
>>
>> ... ?
>
> In fact using do/while(0) is what I first wrote.  But then
> I thought, oh wait, what if an overzealous compiler gives
> a warning because the while() expression is always false? :-/
>
> It's because of examples like this that I am wary of rules
> like "enable all warnings" and "treat any warning condition
> as an error."  I recently ran across a set of coding standard
> rules that included these rules:  not just /some/ warning
> conditions, but ALL warning conditions.  I still don't know
> if they were literally serious.  (And my understanding is
> clang has a -Weverything option, which enables all warning
> conditions that clang is able to test for, no matter how
> silly.)

I've worked under such coding standards.  Perhaps surprisingly, I
haven't found them to be terribly inconvenient.  I rarely ran into
a warning that was inordinately difficult to avoid.   I can see that
"clang -Weverything" would cause problems.

The most common inconvenience was that if I experimentally commented
out some code, and it caused some variable not to be referenced,
the build would fail.  (I could just add `(void)foo;` to avoid that.)
To be clear, this was not code that I intended to commit.

I can imagine that there could be problems if a newer version of the
compiler produced new warnings, but we didn't often change compilers.

(In one obscure case, I wrote a wrapper script that could be
installed in $PATH as "gcc" that would invoke the real gcc and
filter out a particular warning.  The wrapper was necessary due to
the behavior of a build script, not to an explicit coding standard.)

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */

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Concatenated if and preprocessor pozz <pozzugno@gmail.com> - 2025-03-13 16:44 +0100
  Re: Concatenated if and preprocessor David Brown <david.brown@hesbynett.no> - 2025-03-13 16:55 +0100
  Re: Concatenated if and preprocessor scott@slp53.sl.home (Scott Lurndal) - 2025-03-13 16:11 +0000
  Re: Concatenated if and preprocessor James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-03-13 12:07 -0400
  Re: Concatenated if and preprocessor Kaz Kylheku <643-408-1753@kylheku.com> - 2025-03-13 16:30 +0000
  Re: Concatenated if and preprocessor bart <bc@freeuk.com> - 2025-03-13 17:29 +0000
  Re: Concatenated if and preprocessor Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-03-13 14:37 -0700
    Re: Concatenated if and preprocessor Lynn McGuire <lynnmcguire5@gmail.com> - 2025-03-13 18:25 -0500
      Re: Concatenated if and preprocessor Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-03-14 09:26 -0700
  Re: Concatenated if and preprocessor James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-03-13 12:19 -0400
  Re: Concatenated if and preprocessor pozz <pozzugno@gmail.com> - 2025-03-14 13:02 +0100
    Re: Concatenated if and preprocessor David Brown <david.brown@hesbynett.no> - 2025-03-14 14:13 +0100
    Re: Concatenated if and preprocessor Dan Purgert <dan@djph.net> - 2025-03-14 13:44 +0000
    Re: Concatenated if and preprocessor Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-03-14 09:44 -0700
      Re: Concatenated if and preprocessor Richard Harnden <richard.nospam@gmail.invalid> - 2025-03-14 18:15 +0000
        Re: Concatenated if and preprocessor Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-03-14 13:40 -0700
          Re: Concatenated if and preprocessor Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-03-14 14:10 -0700
            Re: Concatenated if and preprocessor Richard Harnden <richard.nospam@gmail.invalid> - 2025-03-14 21:31 +0000
              Re: Concatenated if and preprocessor Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-03-14 15:29 -0700
                Re: Concatenated if and preprocessor David Brown <david.brown@hesbynett.no> - 2025-03-15 17:32 +0100
            Re: Concatenated if and preprocessor Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-03-14 15:57 -0700
              Re: Concatenated if and preprocessor Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-03-14 16:27 -0700
                Re: Concatenated if and preprocessor scott@slp53.sl.home (Scott Lurndal) - 2025-03-15 15:06 +0000
                Re: Concatenated if and preprocessor Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-03-15 08:49 -0700
                Re: Concatenated if and preprocessor scott@slp53.sl.home (Scott Lurndal) - 2025-03-15 17:28 +0000
            Re: Concatenated if and preprocessor David Brown <david.brown@hesbynett.no> - 2025-03-15 17:28 +0100
        Re: Concatenated if and preprocessor Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-03-15 07:03 +0000
    Re: Concatenated if and preprocessor Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-03-14 11:10 -0700
    Re: Concatenated if and preprocessor James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-03-14 23:20 -0400

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