Re: Problem with the function that should display new letter

From	Steve Thompson <stevet810@gmail.com>
Newsgroups	comp.lang.c
Subject	Re: Problem with the function that should display new letter
Date	2015-11-01 00:06 +0000
Organization	Friends of the Galactic Collective
Message-ID	<2yxQ2F.HV1.7nao6@gmail.com> (permalink)
References	<35a13b2e-2412-40ea-89e4-1985879e542c@googlegroups.com> <035ed14d-a9c3-4f6a-bd35-ce64042d012b@googlegroups.com> <ZUvo1a.wFU.FTIiF@gmail.com> <n12g5m$nu6$1@dont-email.me> <f7d58a48-4360-43a5-9591-a0e6c601153c@googlegroups.com>

Show all headers | View raw

On Sat, Oct 31, 2015 at 11:28:21AM -0700, supercat@casperkitty.com wrote:
> On Saturday, October 31, 2015 at 8:39:16 AM UTC-5, Bart wrote:
> > On 30/10/2015 23:29, Steve Thompson wrote:
> > > First, I have found a few cases where the ability to use GCC macros as
> > > expressions is unavoidable.  These are macros encapsulated with ({ ...
> > > }).
> > 
> > (Do you mean being to include any compound statement inside an 
> > expression? If so that's nothing to do with macros.)
> 
> I think Mr. Thompson probably meant "statements", but it should be noted
> that one of the most useful purposes for that syntax is within macros, e.g.
> something like [untested]
> 
>     #define bitswap32(x) \
>       ({ __builtin_const((x)) ? bitswap_const32(x) : bitswap_gen32(x); })
> 
> would accept a 32-bit argument and then either invoke a macro which will
> yield a constant value if invoked on one, but perform inefficiently if
> invoked on a non-constant, or else call a function which will work
> efficiently on non-constant values but would waste time if invoked on a
> constant and would not return a compile-time constant result in any case.
> 
> I don't think there's any way to achieve similar semantics in any form of
> standard C.

If you examine the macro I included in a recent reply to Ben you
should see that I coerce the compiler into doing something similar
with the min/max values, which (ought to, or will if it needs fixing)
resolve to the correct values regardless of the signedness of the
variable types used as arguments to the macro, at least as long as
they are integer types.  In that instance I am leveraging the
preprocessor to resolve expressions into constant values which are
context dependent, and the relying on the optimizer to eliminate
redundant code in the macro.



Regards,

Steve Thompson

-- 
"If I had a nickel for every time some idiot called me about a
computer problem that turned out to be user error, I would be able to
retire and spend the rest of my days cultivating clues in my backyard
hillside garden."  -- MysteryDog in 24hoursupport.helpdesk.

Thread

Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 09:52 -0700
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 10:06 -0700
    Re: Problem with the function that should display new letter John Gordon <gordon@panix.com> - 2015-10-27 17:16 +0000
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 11:28 -0700
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 10:09 -0700
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 10:12 -0700
    Re: Problem with the function that should display new letter Barry Schwarz <schwarzb@dqel.com> - 2015-10-27 13:12 -0700
      Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-10-27 13:23 -0700
        Re: Problem with the function that should display new letter Keith Thompson <kst-u@mib.org> - 2015-10-27 13:49 -0700
          Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-27 21:27 +0000
            Re: Problem with the function that should display new letter Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2015-10-27 18:00 -0400
            Re: Problem with the function that should display new letter glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-10-28 02:53 +0000
              Re: Problem with the function that should display new letter Robert Wessel <robertwessel2@yahoo.com> - 2015-10-28 00:43 -0500
              Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 06:08 +0000
                Re: Problem with the function that should display new letter glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-10-28 08:44 +0000
            Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-28 09:26 +0100
              Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 08:44 +0000
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-28 10:40 +0100
                Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-10-28 06:44 -0700
              Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-10-28 06:35 -0700
  Re: Problem with the function that should display new letter "D. Aaron Sawyer" <aaron@110.net> - 2015-10-27 13:40 -0400
    Re: Problem with the function that should display new letter "D. Aaron Sawyer" <aaron@110.net> - 2015-10-27 13:47 -0400
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 11:38 -0700
        Re: Problem with the function that should display new letter "D. Aaron Sawyer" <aaron@110.net> - 2015-10-27 16:46 -0400
    Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 11:39 -0700
  Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-27 18:20 +0000
    Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 11:36 -0700
    Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 12:09 -0700
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 11:51 -0700
  Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-27 19:25 +0000
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-27 12:27 -0700
    Re: Problem with the function that should display new letter Ian Collins <ian-news@hotmail.com> - 2015-10-28 10:07 +1300
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-28 00:50 -0700
        Re: Problem with the function that should display new letter Ian Collins <ian-news@hotmail.com> - 2015-10-28 21:04 +1300
          Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-28 01:13 -0700
          Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 10:40 +0000
            Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 11:02 +0000
            Re: Problem with the function that should display new letter Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-28 11:28 +0000
              Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 11:57 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 12:53 +0000
                Re: Problem with the function that should display new letter Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-28 13:33 +0000
        Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 08:35 +0000
          Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 10:59 +0000
            Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 11:04 +0000
              Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 11:38 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 11:43 +0000
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 12:10 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 12:58 +0000
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 13:55 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 14:02 +0000
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 15:01 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 15:44 +0000
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 16:22 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 16:26 +0000
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 16:44 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 18:45 +0000
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 19:26 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-28 20:44 +0000
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-28 22:59 +0100
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 22:48 +0000
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-29 01:14 +0100
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-29 01:07 +0000
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-29 14:07 +0100
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-29 13:57 +0000
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-29 16:22 +0100
                Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-10-29 08:38 -0700
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-29 17:25 +0100
                Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-10-29 12:46 -0700
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-30 09:03 +0100
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-29 19:19 +0000
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-30 09:54 +0100
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-30 12:20 +0000
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-29 21:36 +0000
                Re: Problem with the function that should display new letter Ian Collins <ian-news@hotmail.com> - 2015-10-30 10:47 +1300
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-29 22:25 +0000
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-30 09:59 +0100
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-30 10:07 +0100
                Re: Problem with the function that should display new letter David Brown <david.brown@hesbynett.no> - 2015-10-28 16:25 +0100
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-28 16:01 +0000
                Re: Problem with the function that should display new letter Keith Thompson <kst-u@mib.org> - 2015-10-28 09:50 -0700
                Re: Problem with the function that should display new letter glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2015-10-28 21:57 +0000
                Re: Problem with the function that should display new letter Geoff <geoff@invalid.invalid> - 2015-10-28 18:25 -0700
                Re: Problem with the function that should display new letter Geoff <geoff@invalid.invalid> - 2015-10-28 18:23 -0700
                Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-29 01:44 +0000
            Re: Problem with the function that should display new letter Keith Thompson <kst-u@mib.org> - 2015-10-28 07:07 -0700
          Re: Problem with the function that should display new letter Tim Rentsch <txr@alumni.caltech.edu> - 2015-10-30 07:07 -0700
            Re: Problem with the function that should display new letter Keith Thompson <kst-u@mib.org> - 2015-10-30 09:08 -0700
              Re: Problem with the function that should display new letter Tim Rentsch <txr@alumni.caltech.edu> - 2015-10-30 14:29 -0700
                Re: Problem with the function that should display new letter Keith Thompson <kst-u@mib.org> - 2015-10-30 16:10 -0700
                Re: Problem with the function that should display new letter Tim Rentsch <txr@alumni.caltech.edu> - 2015-10-30 20:27 -0700
                Re: Problem with the function that should display new letter Keith Thompson <kst-u@mib.org> - 2015-10-31 12:40 -0700
                Re: Problem with the function that should display new letter Tim Rentsch <txr@alumni.caltech.edu> - 2015-11-02 02:16 -0800
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 03:36 -0700
    Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 10:46 +0000
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 03:56 -0700
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 04:00 -0700
        Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 11:02 +0000
          Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 04:05 -0700
            Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 11:14 +0000
          Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 04:14 -0700
            Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-29 11:26 +0000
            Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 11:26 +0000
              Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 05:29 -0700
                Re: Problem with the function that should display new letter James Kuyper <jameskuyper@verizon.net> - 2015-10-29 09:23 -0400
                Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 07:44 -0700
                Re: Problem with the function that should display new letter James Kuyper <jameskuyper@verizon.net> - 2015-10-29 11:39 -0400
                Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 09:52 -0700
                Re: Problem with the function that should display new letter Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-29 16:02 +0000
                Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 09:56 -0700
                Re: Problem with the function that should display new letter James Kuyper <jameskuyper@verizon.net> - 2015-10-29 13:41 -0400
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 17:46 +0000
                Re: Problem with the function that should display new letter Udyant Wig <udyantw@gmail.com> - 2015-10-30 00:14 +0530
                Re: Problem with the function that should display new letter raltbos@xs4all.nl (Richard Bos) - 2015-10-29 19:30 +0000
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 22:08 +0000
                Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 22:28 -0700
                Re: Problem with the function that should display new letter Tim Rentsch <txr@alumni.caltech.edu> - 2015-10-30 08:10 -0700
                Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-10-30 08:56 -0700
                Re: Problem with the function that should display new letter Tim Rentsch <txr@alumni.caltech.edu> - 2015-10-30 13:18 -0700
                Re: Problem with the function that should display new letter Ian Collins <ian-news@hotmail.com> - 2015-10-30 09:11 +1300
                Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 01:21 -0700
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 04:04 -0700
        Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 11:11 +0000
          Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 04:19 -0700
            Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 11:24 +0000
              Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 05:26 -0700
                Re: Problem with the function that should display new letter Keith Thompson <kst-u@mib.org> - 2015-10-29 08:31 -0700
            Re: Problem with the function that should display new letter James Kuyper <jameskuyper@verizon.net> - 2015-10-29 09:42 -0400
              Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 08:31 -0700
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-29 10:17 -0700
    Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-29 17:36 +0000
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 01:18 -0700
        Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-30 08:36 +0000
          Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-30 08:38 +0000
          Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 02:26 -0700
            Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-30 09:32 +0000
              Re: Problem with the function that should display new letter Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-30 13:39 +0000
          Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 03:59 -0700
            Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-30 11:18 +0000
              Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 06:24 -0700
                Re: Problem with the function that should display new letter James Kuyper <jameskuyper@verizon.net> - 2015-10-30 14:18 -0400
              Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 06:34 -0700
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-30 13:39 +0000
                Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 06:57 -0700
                Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-11-01 09:06 +0000
            Re: Problem with the function that should display new letter Keith Thompson <kst-u@mib.org> - 2015-10-30 08:49 -0700
              Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 10:18 -0700
    Re: Problem with the function that should display new letter Barry Schwarz <schwarzb@dqel.com> - 2015-10-29 11:48 -0700
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 01:23 -0700
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 01:42 -0700
    Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-30 09:13 +0000
    Re: Problem with the function that should display new letter Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-30 10:17 +0000
      Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-30 10:23 +0000
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 06:39 -0700
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 06:45 -0700
    Re: Problem with the function that should display new letter Richard Heathfield <rjh@cpax.org.uk> - 2015-10-30 13:55 +0000
      Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-30 07:05 -0700
    Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-10-30 23:29 +0000
      Re: Problem with the function that should display new letter Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-31 01:14 +0000
        Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-10-31 17:02 +0000
          Re: Problem with the function that should display new letter Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-31 18:05 +0000
            Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-10-31 23:46 +0000
              Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-11-01 08:46 -0800
                Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-11-01 23:43 +0000
                Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-11-01 16:05 -0800
              Re: Problem with the function that should display new letter Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-11-01 21:41 +0000
                Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-11-01 22:46 +0000
          Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-31 18:22 +0000
            Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-10-31 23:57 +0000
        Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-10-31 17:20 +0000
      Re: Problem with the function that should display new letter Bartc <bc@freeuk.com> - 2015-10-31 13:38 +0000
        Re: Problem with the function that should display new letter supercat@casperkitty.com - 2015-10-31 11:28 -0700
          Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-11-01 00:06 +0000
        Re: Problem with the function that should display new letter Steve Thompson <stevet810@gmail.com> - 2015-10-31 17:58 +0000
  Re: Problem with the function that should display new letter Alla _ <modelling.data@gmail.com> - 2015-10-31 01:14 -0700

csiph-web