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Re: Question about #error

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On Wednesday, March 27, 2019 at 9:06:47 AM UTC-7, Kenny McCormack wrote:
> (Using gcc on Linux)
> 
> I always assumed that #error would abort the compilation right then and
> there, rather than try to continue and report other errors.  Since,
> conceptually, pre-processing happens first before any "real" compilation,
> you would think that if the pre-processor hits a #error directive, it would
> abort there before any actual syntactual analysis was done.
> 
> However, I had a construct like this:
> 
> #if something == foo
> int i;
> #elif something == bar
> double i;
> #else
> #error "It has to be either foo or bar"
> #endif
> /* Code that uses "i" */
> 
> When I compile it, and something is not either foo or bar, I get the #error
> message displayed, then I get complaints about "i" not being defined.
> 
> As I say, this is not what I'd expect.
> 
> What is going on?
> 
> 
> -- 

You first must ask yourself "Would Jesus approve of this?"

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Question about #error gazelle@shell.xmission.com (Kenny McCormack) - 2019-03-27 16:06 +0000
  Re: Question about #error Chad <cdalten@gmail.com> - 2019-03-27 10:21 -0700
  Re: Question about #error scott@slp53.sl.home (Scott Lurndal) - 2019-03-27 17:35 +0000
    Re: Question about #error nobody@example.org (Scott) - 2019-03-28 04:33 +0000
      Re: Question about #error Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-04-07 00:15 -0700
        Re: Question about #error gazelle@shell.xmission.com (Kenny McCormack) - 2019-04-07 10:22 +0000
          Re: Question about #error nobody@example.org (Scott) - 2019-04-07 17:10 +0000
  Re: Question about #error Bart <bc@freeuk.com> - 2019-03-27 17:52 +0000
  Re: Question about #error luser droog <luser.droog@gmail.com> - 2019-03-27 12:36 -0700
    Re: Question about #error luser droog <luser.droog@gmail.com> - 2019-03-27 12:47 -0700
  Re: Question about #error John Bode <jfbode1029@gmail.com> - 2019-03-27 14:28 -0700
    Re: Question about #error David Brown <david.brown@hesbynett.no> - 2019-03-27 22:38 +0100
  Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-03-28 13:59 -0700
    Re: Question about #error Keith Thompson <kst-u@mib.org> - 2019-03-28 14:28 -0700
      Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-03-29 07:09 -0700
        Re: Question about #error James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-03-29 08:05 -0700
          Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-03-29 12:08 -0700
            Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-03-29 12:15 -0700
            Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-03-29 12:53 -0700
          Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-03-30 14:40 -0700
            Re: Question about #error Keith Thompson <kst-u@mib.org> - 2019-03-30 15:19 -0700
              Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-03-30 16:17 -0700
                Re: Question about #error scott@slp53.sl.home (Scott Lurndal) - 2019-03-31 19:12 +0000
                Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-04-01 04:32 -0700
              Re: Question about #error David Brown <david.brown@hesbynett.no> - 2019-03-31 20:17 +0200
                Re: Question about #error Richard Damon <Richard@Damon-Family.org> - 2019-03-31 15:09 -0400
                Re: Question about #error David Brown <david.brown@hesbynett.no> - 2019-03-31 21:46 +0200
                Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-04-01 04:36 -0700
            Re: Question about #error James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-04-02 17:47 -0700
              Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-04-03 05:31 -0700
                Re: Question about #error James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-04-03 06:46 -0700
                Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-04-03 07:44 -0700
                Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-04-03 09:46 -0700
    Re: Question about #error scott@slp53.sl.home (Scott Lurndal) - 2019-03-28 21:29 +0000
    Re: Question about #error Thiago Adams <thiago.adams@gmail.com> - 2019-03-29 07:32 -0700

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