Path: csiph.com!goblin1!goblin.stu.neva.ru!usenet.stanford.edu!not-for-mail
From: Koichi Murase <myoga.murase@gmail.com>
Newsgroups: gnu.bash.bug
Subject: Re: Incorrect / Inconsistent behavior with nameref assignments in functions
Date: Sat, 29 Aug 2020 08:46:27 +0900
Lines: 41
Approved: bug-bash@gnu.org
Message-ID: <mailman.1644.1598658404.2469.bug-bash@gnu.org>
References: <a20e4692-69b3-9836-4861-3e822e407ef7@binarus.de> <CAFLRLk8xc4CAR7X_g-B-QMCNtvzVkv5E9kf3EUiD_JUACAfwDA@mail.gmail.com>
NNTP-Posting-Host: lists.gnu.org
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Cc: bug-bash@gnu.org, bash@packages.debian.org
To: Binarus <lists@binarus.de>
Envelope-to: bug-bash@gnu.org
In-Reply-To: <a20e4692-69b3-9836-4861-3e822e407ef7@binarus.de>
Received-SPF: pass client-ip=2a00:1450:4864:20::642; envelope-from=myoga.murase@gmail.com; helo=mail-ej1-x642.google.com
X-Spam_score_int: -20
X-Spam_score: -2.1
X-Spam_bar: --
X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no
X-Spam_action: no action
X-BeenThere: bug-bash@gnu.org
X-Mailman-Version: 2.1.23
Precedence: list
List-Id: Bug reports for the GNU Bourne Again SHell <bug-bash.gnu.org>
List-Unsubscribe: <https://lists.gnu.org/mailman/options/bug-bash>, <mailto:bug-bash-request@gnu.org?subject=unsubscribe>
List-Archive: <https://lists.gnu.org/archive/html/bug-bash>
List-Post: <mailto:bug-bash@gnu.org>
List-Help: <mailto:bug-bash-request@gnu.org?subject=help>
List-Subscribe: <https://lists.gnu.org/mailman/listinfo/bug-bash>, <mailto:bug-bash-request@gnu.org?subject=subscribe>
X-Mailman-Original-Message-ID: <CAFLRLk8xc4CAR7X_g-B-QMCNtvzVkv5E9kf3EUiD_JUACAfwDA@mail.gmail.com>
X-Mailman-Original-References: <a20e4692-69b3-9836-4861-3e822e407ef7@binarus.de>
Xref: csiph.com gnu.bash.bug:16837

2020-08-28 22:04 Binarus <lists@binarus.de>:
> Description:
> ------------
>
> Under certain circumstances, assignments of namerefs to local variables
> in functions behaves in a way which makes namerefs completely useless.
> Furthermore, the behavior is not consistent.

This is actually not related to namerefs and has already been fixed in
Bash 5.1 and the devel branch.  Think about the following codes:

  a=1; f1() { local a=$a; local; }; f1
  a=2; f2() { local -a a=("$a"); local; }; f2

The results for `f1' are the same for all the Bash versions
2.0..devel, but the results for `f2' varies in versions.  Here is the
summary of the results from the different versions of Bash:

- 2.0..3.0: f1: a=1, f2: a=([0]="1")
- 3.1:      f2: a=1, f2: a=([0]="")
- 3.2..4.2: f1: a=1, f2: a=([0]="1")
- 4.3..5.0: f1: a=1, f2: a=([0]="")
- 5.1..dev: f1: a=1, f2: a=([0]="1")

I checked the detailed changes.  The behavior of `f2' in 3.1 was
reported as a bug in the following thread.

  https://lists.gnu.org/archive/html/bug-bash/2006-05/msg00025.html

It was fixed in 8b35878f (commit bash-20060504 snapshot).  However,
the bug seems to be introduced again in 36eb585c (commit bash-20121221
snapshot).  This regression has been reported at

  https://savannah.gnu.org/support/index.php?109669

Finally, it was again fixed in c6c7ae81 (commit bash-20200427
snapshot).

--
Koichi