Subject: bug#39118: Segfault while building on 64-bit Cygwin

From: John Cowan <[email-masked]>
Date: Wed, 5 Feb 2020 16:11:04 -0500

On Mon, Feb 3, 2020 at 5:11 PM szgyg <[email-masked]> wrote:

On Fri, Jan 31, 2020 at 09:23:19AM -0500, John Cowan wrote:
> > Aaaand... Cygwin doesn't do core dumps. Under the skin it's WIndows,
> after
> > all.  This is what I get when I specify ulimit -c unlimited and rebuild:
> > [...]
>
> Please see my previous mail on how to get a real core dump on cygwin
> https://debbugs.gnu.org/cgi/bugreport.cgi?bug=39118#28

Okay, I looked at that page.  However, Cygwin's dumper requires you to know
the Windows PID of the process to dump.  Clearly it is intended for a
long-running process such as a server process, which you can force to core
dump, as if by "/bin/kill -SIGSEGV pid"; it is not suitable for a process
that gets a segmentation violation for internal reasons.  In any case, when
building, I have no idea of the pid of the process which is dumping; it
starts up and then dumps immediately.

John Cowan          http://vrici.lojban.org/~cowan        [email-masked]
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