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Groups > comp.lang.c > #11755

Re: Multi-instructions macro and compiler warning

From Ian Collins <ian-news@hotmail.com>
Newsgroups comp.lang.c
Subject Re: Multi-instructions macro and compiler warning
Date 2011-10-16 20:31 +1300
Message-ID <9fvfilF3u9U2@mid.individual.net> (permalink)
References <j7e002$64g$1@nnrp.ngi.it>

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On 10/16/11 08:09 PM, pozz wrote:
> I'm trying to increase the warning level during compilation.  My goal is
> to reach the maximum warning level without any warning message after
> compilation.  I think this is a Good Thing to do when programming.
>
> After changing warning level from 4 to 5, I received many warning
> messages of the type
>
>     W1207C: conditional expression is constant: dowhile
>
> Those messages refer to multi-instructions macros defined as below:
>
>     #define MACRO(a, b)  do { foo(a); bar(b); } while(0)
>
> Many times I read to use the trick do/while(0) to write
> multi-instruction macros to avoid other problems during compilation.  In
> this way, I can use MACRO() at any point where I could use a normal
> function.
>
> How can I avoid the warning message W1207C?  I'm using an embedded
> microcontroller C compiler from Fujitsu, named Softune.

Use a function.  Any decent compiler will inline something that trivial.

-- 
Ian Collins

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Thread

Multi-instructions macro and compiler warning pozz <pozzugno@gmail.com> - 2011-10-16 09:09 +0200
  Re: Multi-instructions macro and compiler warning Ian Collins <ian-news@hotmail.com> - 2011-10-16 20:31 +1300
    Re: Multi-instructions macro and compiler warning pozz <pozzugno@gmail.com> - 2011-10-16 09:41 +0200
      Re: Multi-instructions macro and compiler warning Ian Collins <ian-news@hotmail.com> - 2011-10-16 20:49 +1300
        Re: Multi-instructions macro and compiler warning pozz <pozzugno@gmail.com> - 2011-10-16 10:16 +0200
          Re: Multi-instructions macro and compiler warning Ian Collins <ian-news@hotmail.com> - 2011-10-16 23:09 +1300
            Re: Multi-instructions macro and compiler warning pozz <pozzugno@gmail.com> - 2011-10-17 02:37 -0700
              Re: Multi-instructions macro and compiler warning Ian Collins <ian-news@hotmail.com> - 2011-10-17 23:04 +1300
              Re: Multi-instructions macro and compiler warning Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-10-17 11:06 +0100
                Re: Multi-instructions macro and compiler warning pozz <pozzugno@gmail.com> - 2011-10-17 03:23 -0700
              Re: Multi-instructions macro and compiler warning Keith Thompson <kst-u@mib.org> - 2011-10-17 12:30 -0700
      Re: Multi-instructions macro and compiler warning "BartC" <bc@freeuk.com> - 2011-10-16 12:47 +0100
        Re: Multi-instructions macro and compiler warning Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-10-16 22:16 +0000
        Re: Multi-instructions macro and compiler warning pozz <pozzugno@gmail.com> - 2011-10-17 02:42 -0700
          Re: Multi-instructions macro and compiler warning "BartC" <bc@freeuk.com> - 2011-10-17 13:10 +0100
      Re: Multi-instructions macro and compiler warning bert <bert.hutchings@btinternet.com> - 2011-10-16 05:33 -0700
  Re: Multi-instructions macro and compiler warning Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-10-16 09:02 -0400
  Re: Multi-instructions macro and compiler warning "christian.bau" <christian.bau@cbau.wanadoo.co.uk> - 2011-10-16 07:40 -0700
    Re: Multi-instructions macro and compiler warning ImpalerCore <jadill33@gmail.com> - 2011-10-17 08:07 -0700
      Re: Multi-instructions macro and compiler warning "christian.bau" <christian.bau@cbau.wanadoo.co.uk> - 2011-10-17 09:25 -0700
        Re: Multi-instructions macro and compiler warning James Kuyper <jameskuyper@verizon.net> - 2011-10-17 12:58 -0400
          Re: Multi-instructions macro and compiler warning Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-10-18 07:43 -0400
            Re: Multi-instructions macro and compiler warning Keith Thompson <kst-u@mib.org> - 2011-10-18 11:52 -0700
        Re: Multi-instructions macro and compiler warning ImpalerCore <jadill33@gmail.com> - 2011-10-17 10:41 -0700
  Re: Multi-instructions macro and compiler warning Jean-Christophe <5.d@free.fr> - 2011-10-16 10:02 -0700
    Re: Multi-instructions macro and compiler warning Kleuskes & Moos <kleuske@somewhere.else.net> - 2011-10-16 17:44 +0000
    Re: Multi-instructions macro and compiler warning Keith Thompson <kst-u@mib.org> - 2011-10-16 13:49 -0700
      Re: Multi-instructions macro and compiler warning Ian Collins <ian-news@hotmail.com> - 2011-10-17 10:00 +1300
  Re: Multi-instructions macro and compiler warning Kenneth Brody <kenbrody@spamcop.net> - 2011-10-17 12:50 -0400
    Re: Multi-instructions macro and compiler warning "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-10-17 14:50 -0400

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