bug#24022: 24.5; C indentation failure

bug#24022: 24.5; C indentation failure

[robgssp]

c-mode fails to indent correctly when a #if is followed by a
comment. Example:

int main() {
#if defined(a) // comment
  if (b) {
  body();
}
#endif
  }

Clearly this isn't the correct indentation. A clean run under -Q behaves
the same way.



In GNU Emacs 24.5.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.20.6)
 of 2016-06-04 on juergen
Windowing system distributor `The X.Org Foundation', version 11.0.11803000
System Description:	Arch Linux

Configured using:
 `configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
 --localstatedir=/var --with-x-toolkit=gtk3 --with-xft
 'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe
 -fstack-protector-strong' CPPFLAGS=-D_FORTIFY_SOURCE=2
 LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro'

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: C/l

Minor modes in effect:
  tooltip-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
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Quit
Auto-saving...

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
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help-fns mail-prsvr mail-utils cc-langs cl-loaddefs cl-lib cc-mode
cc-fonts easymenu cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine
cc-vars cc-defs time-date tooltip electric uniquify ediff-hook vc-hooks
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romanian slovak czech european ethiopic indian cyrillic chinese
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move-toolbar gtk x-toolkit x multi-tty emacs)

Memory information:
((conses 16 103095 4287)
 (symbols 48 20066 0)
 (miscs 40 40 160)
 (strings 32 16635 4321)
 (string-bytes 1 568293)
 (vectors 16 11333)
 (vector-slots 8 412487 3082)
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bug#24022: 24.5; C indentation failure

[Alan Mackenzie]

Hello, robgssp.

In article <mailman.1656.1468874050.26859.bug-gnu-emacs@gnu.org> you wrote:

> c-mode fails to indent correctly when a #if is followed by a
> comment. Example:

> int main() {
> #if defined(a) // comment
>   if (b) {
>   body();
> }
> #endif
>   }

> Clearly this isn't the correct indentation. A clean run under -Q behaves
> the same way.

Yes.

Thanks for taking the trouble to report this problem, and thanks even
more for cutting the source down to a small, easy to handle test case.

There have been extensive changes to CC Mode since the release of Emacs
24.5, and the problem isn't apparent in more recent versions.  Bisecting
the changes in mercurial suggest that this bug was "solved" by a commit on
2016-05-29.

I've tried to adapt this commit so that it will apply to the Emacs 24.5
sources, but the changes are just too many for this to be practicable.

Would it be OK for me to send you a tarball of the up-to-date CC Mode
sources (~1.34 Mb) so that you could build these on Emacs 24.5 and check
that the error really has been fixed (and not just in the cut down test
case you've sent me)?

> In GNU Emacs 24.5.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.20.6)
>  of 2016-06-04 on juergen
> Windowing system distributor `The X.Org Foundation', version 11.0.11803000
> System Description:     Arch Linux

> Configured using:
>  `configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
>  --localstatedir=/var --with-x-toolkit=gtk3 --with-xft
>  'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe
>  -fstack-protector-strong' CPPFLAGS=-D_FORTIFY_SOURCE=2
>  LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro'

> Important settings:
>   value of $LANG: en_US.UTF-8
>   locale-coding-system: utf-8-unix

> Major mode: C/l

-- 
Alan Mackenzie (Nuremberg, Germany).

bug#24022: 24.5; C indentation failure

[Stefan Kangas]

Alan Mackenzie <acm@muc.de> writes:

> Hello, robgssp.
>
> In article <mailman.1656.1468874050.26859.bug-gnu-emacs@gnu.org> you wrote:
>
>> c-mode fails to indent correctly when a #if is followed by a
>> comment. Example:
>
>> int main() {
>> #if defined(a) // comment
>>   if (b) {
>>   body();
>> }
>> #endif
>>   }
>
>> Clearly this isn't the correct indentation. A clean run under -Q behaves
>> the same way.
>
> Yes.
>
> Thanks for taking the trouble to report this problem, and thanks even
> more for cutting the source down to a small, easy to handle test case.
>
> There have been extensive changes to CC Mode since the release of Emacs
> 24.5, and the problem isn't apparent in more recent versions.  Bisecting
> the changes in mercurial suggest that this bug was "solved" by a commit on
> 2016-05-29.
>
> I've tried to adapt this commit so that it will apply to the Emacs 24.5
> sources, but the changes are just too many for this to be practicable.
>
> Would it be OK for me to send you a tarball of the up-to-date CC Mode
> sources (~1.34 Mb) so that you could build these on Emacs 24.5 and check
> that the error really has been fixed (and not just in the cut down test
> case you've sent me)?

Hi Alan,

It looks like this has been fixed, but you were awaiting some further
verification from the reporter.  Did you ever get such verification?

If not, perhaps we should just close this if you can't reproduce it.

I can't reproduce it on current master using the example given above.

Best regards,
Stefan Kangas

bug#24022: 24.5; C indentation failure

[Alan Mackenzie]

Hello, Stefan

On Sun, Sep 29, 2019 at 07:02:35 +0200, Stefan Kangas wrote:
> Alan Mackenzie <acm@muc.de> writes:

> > Hello, robgssp.

> > In article <mailman.1656.1468874050.26859.bug-gnu-emacs@gnu.org> you wrote:

> >> c-mode fails to indent correctly when a #if is followed by a
> >> comment. Example:

> >> int main() {
> >> #if defined(a) // comment
> >>   if (b) {
> >>   body();
> >> }
> >> #endif
> >>   }

> >> Clearly this isn't the correct indentation. A clean run under -Q behaves
> >> the same way.

> > Yes.

> > Thanks for taking the trouble to report this problem, and thanks even
> > more for cutting the source down to a small, easy to handle test case.

> > There have been extensive changes to CC Mode since the release of Emacs
> > 24.5, and the problem isn't apparent in more recent versions.  Bisecting
> > the changes in mercurial suggest that this bug was "solved" by a commit on
> > 2016-05-29.

> > I've tried to adapt this commit so that it will apply to the Emacs 24.5
> > sources, but the changes are just too many for this to be practicable.

> > Would it be OK for me to send you a tarball of the up-to-date CC Mode
> > sources (~1.34 Mb) so that you could build these on Emacs 24.5 and check
> > that the error really has been fixed (and not just in the cut down test
> > case you've sent me)?

> Hi Alan,

> It looks like this has been fixed, but you were awaiting some further
> verification from the reporter.  Did you ever get such verification?

I never did, no.

> If not, perhaps we should just close this if you can't reproduce it.

We should indeed close it.  The problem has been solved.

> I can't reproduce it on current master using the example given above.

Indeed.  Does this go under "wontfix" or "solved", or some other status?
I marked it as "wontfix" in my own bug log, since I couldn't reasonably
fix it in Emacs 24.5.

> Best regards,
> Stefan Kangas

-- 
Alan Mackenzie (Nuremberg, Germany).

bug#24022: 24.5; C indentation failure

[Stefan Kangas]

Hi Alan,

Alan Mackenzie <acm@muc.de> writes:

> > If not, perhaps we should just close this if you can't reproduce it.
>
> We should indeed close it.  The problem has been solved.

Great.

> > I can't reproduce it on current master using the example given above.
>
> Indeed.  Does this go under "wontfix" or "solved", or some other status?
> I marked it as "wontfix" in my own bug log, since I couldn't reasonably
> fix it in Emacs 24.5.

If we know a specific version when it was fixed, I guess "close 24022
25.1" is best (if 25.1 is indeed the version).  Otherwise, I see no
reason why we can't close it without any specific tag.

Best regards,
Stefan Kangas

bug#24022: 24.5; C indentation failure

[Stefan Kangas]

Stefan Kangas <stefan@marxist.se> writes:

>> > If not, perhaps we should just close this if you can't reproduce it.
>>
>> We should indeed close it.  The problem has been solved.
>
> Great.
>
>> > I can't reproduce it on current master using the example given above.
>>
>> Indeed.  Does this go under "wontfix" or "solved", or some other status?
>> I marked it as "wontfix" in my own bug log, since I couldn't reasonably
>> fix it in Emacs 24.5.
>
> If we know a specific version when it was fixed, I guess "close 24022
> 25.1" is best (if 25.1 is indeed the version).  Otherwise, I see no
> reason why we can't close it without any specific tag.

Closing this now.

Best regards,
Stefan Kangas