Re: how to make a macro work as a single line if stmt without braces

From	Michael S <already5chosen@yahoo.com>
Newsgroups	comp.lang.c
Subject	Re: how to make a macro work as a single line if stmt without braces
Date	2024-09-22 19:27 +0300
Organization	A noiseless patient Spider
Message-ID	<20240922192726.000061fc@yahoo.com> (permalink)
References	(1 earlier) <vcm16e$1hm2u$1@dont-email.me> <vcn6m8$1n1vu$1@dont-email.me> <vcp0rq$26p7b$1@dont-email.me> <20240922080605.59@kylheku.com> <vcpeo0$28shf$1@dont-email.me>

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On Sun, 22 Sep 2024 16:56:47 +0100
Bart <bc@freeuk.com> wrote:

> On 22/09/2024 16:11, Kaz Kylheku wrote:
> > On 2024-09-22, David Brown <david.brown@hesbynett.no> wrote:  
> >> I am not suggesting overuse of braces.  I am suggesting /good/ use
> >> of them.
> >>
> >> <https://www.synopsys.com/blogs/software-security/understanding-apple-goto-fail-vulnerability-2.html>
> >>
> >> That's perhaps the most famous example of the havoc caused by
> >> omitting useful braces.
> >>
> >> Consistency and clarity is important.  So is maintainability.
> >> Suppose, for example, you want to add a line "attempts++;"
> >> alongside the "ok++;" line.  When the braces are there, the change
> >> is exactly that - add the new line you want.  Without the original
> >> braces, you are now making changes to the structural syntax of the
> >> code as well when you add in original braces - or you are making a
> >> mistake in the code.  
> > 
> > My super advanced text editor from the future isn't letting me do
> > that:
> > 
> >    if (failed)
> >      WARN("failed because...");
> >    else
> >      ok++;
> >    attempts++; // automatic deindent
> > 
> > When I add a line after ok++, it deindents it to be at the same
> > indentation level as the if, before letting me type any content
> > into it.
> > 
> > OK, I lied about the super advanced from the future. It's just Vim.
> > 
> > Also GCC has been able to diagnose misleading indentation for some
> > years now.
> > 
> > Between those two, there is nothing to worry about; just
> > concentrate on whether it looks prettier without the braces or with.
> >   
> 
> So, everyone has to write code exactly to the C standard.
> 
> But when it comes to more practical matters, it's OK to depend on the 
> arbitrary characteristics and abilities of whichever one of 1001 
> different text editors we happen to be using.
> 
> Or we have to use a specific compiler with a specific set of options.
> 
>  > Also GCC has been able to diagnose misleading indentation for some
>  > years now.  
> 
> How many years was that out of the last 52? How exactly do you turn
> it on? Since -Wall -Wpedantic -Wextra doesn't report it.
> 

My gcc warns just fine.

void bar(int);
int foo(int x) {
  if (x)
    bar(x);
    x -= 1;
  return x;
}

gcc -c -Wall foo.c

foo.c: In function 'foo':
foo.c:3:3: warning: this 'if' clause does not guard...
[-Wmisleading-indentation] 3 |   if (x)
      |   ^~
foo.c:5:5: note: ...this statement, but the latter is misleadingly
indented as if it were guarded by the 'if'
    5 |     x -= 1;
      |     ^


> It is a failure in the design of the language. You can't really
> depend on ad hoc features of the tools you use to create and compile
> source code.
> 
> At least guidelines can be used such as always using braces, then
> errors can occur less often.
> 
> (I've been bitten by this endless times when trying to add debugging 
> statements to existing code. If that code consistently used braces,
> then it wouldn't happen.)

I wonder why I was not bitten by that more than, may be, 5 times in
30+ years. Probably, I am doing something wrong.

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how to make a macro work as a single line if stmt without braces Mark Summerfield <mark@qtrac.eu> - 2024-09-21 07:35 +0000
  Re: how to make a macro work as a single line if stmt without braces Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-09-21 08:10 +0000
  Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-21 10:47 +0200
    Re: how to make a macro work as a single line if stmt without braces Andrey Tarasevich <andreytarasevich@hotmail.com> - 2024-09-21 12:27 -0700
      Re: how to make a macro work as a single line if stmt without braces Bart <bc@freeuk.com> - 2024-09-21 21:11 +0100
      Re: how to make a macro work as a single line if stmt without braces Opus <ifonly@youknew.org> - 2024-09-21 22:39 +0200
      Re: how to make a macro work as a single line if stmt without braces Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-09-21 14:54 -0700
        Re: how to make a macro work as a single line if stmt without braces Andrey Tarasevich <andreytarasevich@hotmail.com> - 2024-09-21 20:05 -0700
          Re: how to make a macro work as a single line if stmt without braces Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-09-21 21:33 -0700
          Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-22 14:15 +0200
          Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-27 03:38 -0700
      Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-22 13:59 +0200
        Re: how to make a macro work as a single line if stmt without braces Kaz Kylheku <643-408-1753@kylheku.com> - 2024-09-22 15:11 +0000
          Re: how to make a macro work as a single line if stmt without braces Bart <bc@freeuk.com> - 2024-09-22 16:56 +0100
            Re: how to make a macro work as a single line if stmt without braces Michael S <already5chosen@yahoo.com> - 2024-09-22 19:27 +0300
              Re: how to make a macro work as a single line if stmt without braces Bart <bc@freeuk.com> - 2024-09-22 17:47 +0100
              Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-24 07:36 -0700
                Re: how to make a macro work as a single line if stmt without braces Andrey Tarasevich <andreytarasevich@hotmail.com> - 2024-09-24 07:52 -0700
                Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-24 17:24 +0200
                Re: how to make a macro work as a single line if stmt without braces Bart <bc@freeuk.com> - 2024-09-24 17:22 +0100
                Re: how to make a macro work as a single line if stmt without braces Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-09-24 12:28 -0700
                Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-27 01:43 -0700
                Re: how to make a macro work as a single line if stmt without braces Bart <bc@freeuk.com> - 2024-09-24 17:35 +0100
                Re: how to make a macro work as a single line if stmt without braces Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-09-24 12:30 -0700
                Re: how to make a macro work as a single line if stmt without braces Bart <bc@freeuk.com> - 2024-09-24 20:42 +0100
                Re: how to make a macro work as a single line if stmt without braces Kaz Kylheku <643-408-1753@kylheku.com> - 2024-09-24 19:59 +0000
                Re: how to make a macro work as a single line if stmt without braces Bart <bc@freeuk.com> - 2024-09-24 21:12 +0100
                Re: how to make a macro work as a single line if stmt without braces Kaz Kylheku <643-408-1753@kylheku.com> - 2024-09-24 22:36 +0000
            Re: how to make a macro work as a single line if stmt without braces Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-09-22 13:39 -0700
              Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-23 08:16 +0200
                Re: how to make a macro work as a single line if stmt without braces Richard Harnden <richard.nospam@gmail.invalid> - 2024-09-23 08:06 +0100
                Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-23 11:14 +0200
                Re: how to make a macro work as a single line if stmt without braces Richard Harnden <richard.nospam@gmail.invalid> - 2024-09-23 11:37 +0100
                Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-23 14:22 +0200
          Modern text editor - 'bout time someone paid attention to keeping the thread title relevant!!! (Was: how to make a macro work as a single line if stmt without braces) gazelle@shell.xmission.com (Kenny McCormack) - 2024-09-22 16:03 +0000
          Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-22 18:03 +0200
      Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-28 05:02 -0700
        Re: how to make a macro work as a single line if stmt without braces Michael S <already5chosen@yahoo.com> - 2024-09-28 20:30 +0300
          Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-28 21:53 -0700
            Re: how to make a macro work as a single line if stmt without braces Michael S <already5chosen@yahoo.com> - 2024-09-29 12:48 +0300
              Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-29 19:18 -0700
              Re: how to make a macro work as a single line if stmt without braces Alan Mackenzie <acm@muc.de> - 2024-09-30 15:05 +0000
        Re: how to make a macro work as a single line if stmt without braces Andrey Tarasevich <andreytarasevich@hotmail.com> - 2024-09-28 21:02 -0700
          Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-28 22:47 -0700
            Re: how to make a macro work as a single line if stmt without braces Andrey Tarasevich <andreytarasevich@hotmail.com> - 2024-09-29 07:41 -0700
              Re: how to make a macro work as a single line if stmt without braces Michael S <already5chosen@yahoo.com> - 2024-09-29 18:04 +0300
              Re: how to make a macro work as a single line if stmt without braces scott@slp53.sl.home (Scott Lurndal) - 2024-09-29 18:30 +0000
              Re: how to make a macro work as a single line if stmt without braces Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-09-29 16:39 -0700
                Re: how to make a macro work as a single line if stmt without braces Kaz Kylheku <643-408-1753@kylheku.com> - 2024-09-30 02:29 +0000
                Re: how to make a macro work as a single line if stmt without braces Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-09-30 11:26 +0200
              Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-29 18:39 -0700
              Re: how to make a macro work as a single line if stmt without braces Kaz Kylheku <643-408-1753@kylheku.com> - 2024-09-30 02:03 +0000
              Re: how to make a macro work as a single line if stmt without braces David Brown <david.brown@hesbynett.no> - 2024-09-30 13:17 +0200
  Re: how to make a macro work as a single line if stmt without braces Bart <bc@freeuk.com> - 2024-09-21 10:13 +0100
    Re: how to make a macro work as a single line if stmt without braces Mark Summerfield <mark@qtrac.eu> - 2024-09-21 09:53 +0000
  Re: how to make a macro work as a single line if stmt without braces Ike Naar <ike@sdf.org> - 2024-09-21 09:15 +0000
    Re: how to make a macro work as a single line if stmt without braces Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-09-21 14:44 -0700
  Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-21 06:07 -0700
    Re: how to make a macro work as a single line if stmt without braces Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-09-21 15:55 -0700
  Re: how to make a macro work as a single line if stmt without braces Andrey Tarasevich <andreytarasevich@hotmail.com> - 2024-09-21 12:17 -0700
  Re: how to make a macro work as a single line if stmt without braces Blue-Maned_Hawk <bluemanedhawk@invalid.invalid> - 2024-09-21 21:18 +0000
    Re: how to make a macro work as a single line if stmt without braces Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-09-24 06:18 -0700

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