DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org D91EA386188A
Subject: Re: Failed assertion dialog box ATTN: Takashi Yano
To: cygwin@cygwin.com
References: <CAH5rLZVNLkwntpF4U-27+KeF_eh30yc2bij_MqejWTxBbdQmdw@mail.gmail.com>
 <20201114034504.GD2905@dimstar.local.net>
 <CAH5rLZV+T7u_u6TgivKA7y2RmBJiySVuUsxPVJQjLsEYoN91_A@mail.gmail.com>
 <20201115044613.GE2905@dimstar.local.net>
 <CAH5rLZV25Z1EcrputHDswkuFRSVi8XJ+oJx5RaR3rYvawqay9w@mail.gmail.com>
 <DM5PR19MB098611D7A5F52EE51A7918B693E40@DM5PR19MB0986.namprd19.prod.outlook.com>
 <DM5PR19MB0986B3BF7499FE71262677FB93E40@DM5PR19MB0986.namprd19.prod.outlook.com>
 <DM5PR19MB0986D551BC9C6DAD28463FC193E00@DM5PR19MB0986.namprd19.prod.outlook.com>
From: Thomas Wolff <towo@towo.net>
Message-ID: <6d8262e3-4206-a05b-5252-f77bef27b0db@towo.net>
Date: Thu, 19 Nov 2020 19:30:20 +0100
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101
 Thunderbird/78.4.3
MIME-Version: 1.0
In-Reply-To: <DM5PR19MB0986D551BC9C6DAD28463FC193E00@DM5PR19MB0986.namprd19.prod.outlook.com>
Precedence: list
Content-Type: text/plain; charset="utf-8"; Format="flowed"
Errors-To: cygwin-bounces@cygwin.com
Sender: "Cygwin" <cygwin-bounces@cygwin.com>
Content-Transfer-Encoding: 8bit


Am 19.11.2020 um 15:21 schrieb André Bleau via Cygwin:
> ...
> Here's some more info:
>
> It seems the bug is related to pseudo-console support; that explains why it is Windows 10 specific.
>
> Experiment:
>
> CYGWIN=disable_pcon /usr/bin/mintty &
>
> In the newly created window:
>
> $ ./a.exe </dev/null >output.txt 2>&1
> Aborted (core dumped)
>
> No message box popup.
>
> $ cat output.txt
> assertion "false" failed: file "assert.cpp", line 3, function: int main()
>
> In the original mintty window, with empty CYGWIN env variable:
>
> $ ./a.exe </dev/null >output.txt 2>&1
> Aborted (core dumped)
>
> A message box pops
>
> AND:
>
> $ cat output.txt
>
>   output.txt  is empty
>
> So, 2 problems here.
>
> In a CMD Window:
>
> set path=%PATH%D:\Cygwin\bin;
> a.exe <NUL: >outcmd.txt 2>&1
>        1 [main] a 759 cygwin_exception::open_stackdumpfile: Dumping stack trace to a.exe.stackdump
>
> type outcmd.txt
> assertion "false" failed: file "assert.cpp", line 3, function: int main()
>        1 [main] a 759 cygwin_exception::open_stackdumpfile: Dumping stack trace to a.exe.stackdump
>
> The bug could be in cygwin or in mintty. Maybe this is something that Thomas Wolff (mintty author) or Takashi Yano  (pseudo-console support expert) would want to look at.
> ---------------------------------------------------------------------------------------
>
> OK, I opened an issue for mintty and it was quickly closed with that quote:
>
> "Quick generic answer: if it's caused by ConPTY support, it's not related to mintty; also mintty never shows any popups.
> Funny thing, though, but really: assert isn't handled by the terminal."
>
> So the issue can only be with pseudo-console support in cygwin.
It does not seem to happen in xterm which is weird.
It does however also happen in rxvt-unicode, xfce4-terminal, and vte.
The message text of the popup can be easily found in cygwin code.
Thomas
--
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