DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 6674E3858D20
Date: Wed, 29 May 2024 19:06:19 +0900
To: cygwin@cygwin.com
Cc: Bruno Haible <bruno@clisp.org>
Subject: Re: multithreading broken in Cygwin 3.5.3
Message-Id: <20240529190619.53c5820ecafcf31909c4320c@nifty.ne.jp>
In-Reply-To: <3631253.RrQHTzY0li@nimes>
References: <3631253.RrQHTzY0li@nimes>
Mime-Version: 1.0
Precedence: list
From: Takashi Yano via Cygwin <cygwin@cygwin.com>
Reply-To: Takashi Yano <takashi.yano@nifty.ne.jp>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Errors-To: cygwin-bounces+archive-cygwin=delorie.com@cygwin.com
Sender: "Cygwin" <cygwin-bounces+archive-cygwin=delorie.com@cygwin.com>

On Thu, 23 May 2024 20:09:09 +0200
Bruno Haible wrote:
> In Cygwin 3.5.3, on different machines, I see 3 Gnulib tests failing by
> timeout that worked perfectly fine in Cygwin 3.4.6 and older:
>   FAIL: test-call_once2.exe
>   FAIL: test-lock.exe
>   FAIL: test-pthread-once2.exe
> 
> Find here attached a simplified version of test-pthread-once2.c.
> Compile and run:
>   $ x86_64-pc-cygwin-gcc -Wall foo.c
>   $ ./a
> 
> Expected behaviour: Termination within 1 minute.
> Actual behaviour:   Terminates by timeout after 10 minutes.
> 
> When I change
>   #define ENABLE_DEBUGGING 0
> to
>   #define ENABLE_DEBUGGING 1
> the test does lots of output and terminates within 20 seconds.
> Therefore I can't really tell where the problem comes from.
> But I do see some changes in
>   $ git diff cygwin-3.4.6 cygwin-3.5.3 winsup/cygwin/thread.cc
>   $ git diff cygwin-3.4.6 cygwin-3.5.3 winsup/testsuite/winsup.api/pthread

Thanks for the report.

As you mentioned in private mail to me, this seems to be a regression of
pthread::once() introduced by
commit 2c5433e5da8216aaf7458e50c63683c68fb0d3e8.

I'll submit a patch for that issue shortly.

-- 
Takashi Yano <takashi.yano@nifty.ne.jp>

-- 
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple