Re: Intentionally unused variable, suppress warnings for just one?

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From	Keith Thompson <kst-u@mib.org>
Newsgroups	comp.lang.c
Subject	Re: Intentionally unused variable, suppress warnings for just one?
Date	Tue, 02 Aug 2016 14:47:18 -0700
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mathog <dmathog@gmail.com> writes:
> This is probably off topic, but somebody here is likely to know how to 
> do this, so...
>
> In some code there is a function:
>
>    SOME_STRUCTURE_TYPE a_structure;
>    int a_result = a_function(&a_structure);
>
> where "a_result" is never referred to again in the rest of the code.
[reasons snipped]

> What I want to do is suppress the warning only for these 10 lines.

This seems to work for gcc, and may work for other compilers as well:

    SOME_STRUCTURE_TYPE a_structure;
    int a_result = a_function(&a_structure);
    (void)a_result;

(I might wonder whether you really should be ignoring the result, but
there's not enough information to speculate.)

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

Thread

Intentionally unused variable, suppress warnings for just one? mathog <dmathog@gmail.com> - 2016-08-02 14:30 -0700
  Re: Intentionally unused variable, suppress warnings for just one? Keith Thompson <kst-u@mib.org> - 2016-08-02 14:47 -0700
    Re: Intentionally unused variable, suppress warnings for just one? mathog <dmathog@gmail.com> - 2016-08-02 15:14 -0700
    Re: Intentionally unused variable, suppress warnings for just one? David Brown <david.brown@hesbynett.no> - 2016-08-03 14:17 +0200
  Re: Intentionally unused variable, suppress warnings for just one? gordonb.sapr8@burditt.org (Gordon Burditt) - 2016-08-02 16:52 -0500
    Re: Intentionally unused variable, suppress warnings for just one? David Brown <david.brown@hesbynett.no> - 2016-08-03 14:21 +0200
    Re: Intentionally unused variable, suppress warnings for just one? James Kuyper <jameskuyper@verizon.net> - 2016-08-03 10:46 -0400

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