GNU bug report logs - #76945
[PATCH] etags: character classes and intervals not working in --regex

Previous Next

Full log

View this message in rfc822 format

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: Vladimir Gorsunov <gorsunov <at> gmail.com>, Richard Stallman <rms <at> gnu.org>, 76945 <at> debbugs.gnu.org
Subject: bug#76945: [PATCH] etags: character classes and intervals not working in --regex
Date: Tue, 11 Mar 2025 10:58:58 -0700

On 2025-03-11 10:41, Eli Zaretskii wrote:
>> Date: Tue, 11 Mar 2025 14:28:45 +0200
>> From: Vladimir Gorsunov <gorsunov <at> gmail.com>
>>
>>     Before commit d904cc83 regex syntax flags used in etags were
>>
>>     RE_CHAR_CLASSES | RE_INTERVALS | RE_SHY_GROUPS | RE_FRUGAL
>>
>>     that got changed to 0. Including a patch that restores
>>     RE_CHAR_CLASSES and RE_INTERVALS and adds check for these features
>>     to the test. As far I can understand from the bug 74861, the
>>     absence of shy groups and non-greedy matching won't be fixed
>>     until Gnulib supports them
> 
> Thanks.
> 
> Paul, any comments?

As I understand it the original design for glibc regex was that Emacs 
was the default, so a flags value of zero meant Emacs. This is why 
RE_SYNTAX_EMACS is 0.

Evidently that design goal no longer holds, so it makes sense to adjust 
Emacs's use of glibc flags to match the behavior of Emacs's only 
regular-expression implementation in emacs/src/regex-emacs.c as best we can.

However, surely this adjustment should be made in Gnulib, not in 
etags.c. That is, gnulib/lib/regex.h (aka emacs/lib/regex.h) should 
#define RE_SYNTAX_EMACS to equal RE_CHAR_CLASSES | RE_INTERVALS, not 
zero. And eventually this change should be migrated back to glibc.

I'll cc this to rms in case he has further comments about this.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.