From: David Stacey <drstacey@tiscali.co.uk>
To: cygwin@cygwin.com
Subject: Re: static vs. shared linking
Date: Wed, 25 Mar 2015 23:28:00 -0000 [thread overview]
Message-ID: <55133B41.80108@tiscali.co.uk> (raw)
In-Reply-To: <55133295.1090105@tiscali.co.uk>
On 25/03/2015 22:11, David Stacey wrote:
> On 25/03/2015 16:59, Warren Young wrote:
>> If that makes the symptom disappear, I wonder if thereâs some problem
>> with a Cygwin *.exe owning a std::string that gets resized by a
>> Cygwin *.dll. If so, that probably*is* a memory ownership
>> coordination problem that affects Cygwin proper.
>
> In order to test your hypothesis about memory ownership, I'll create a
> test that malloc(3)s some memory in the .exe and free(3)s it in a
> shared library; Corinna showed that the crash was coming from an
> abort() in free(). However, I can't believe it's that simple - you'd
> think there would be dozens of programmes crashing for this reason.
Indeed. I created a very simple test that alloc(3)s memory in main() and
then free(3)s it in a shared library. That works fine. So there's more
to it than that :-(
Dave.
// crash_library.h
#ifndef CRASH_LIBRARY_H
#define CRASH_LIBRARY_H
extern void Crash(unsigned short *ptr);
#endif // CRASH_LIBRARY_H
// crash_library.cpp
#include "crash_library.h"
#include <stdlib.h>
void Crash(unsigned short *ptr)
{
free(ptr);
}
// main.cpp
#include "crash_library.h"
#include <stdlib.h>
int main()
{
unsigned short*ptr = (unsigned short*)malloc(sizeof(unsigned short));
Crash(ptr);
return 0;
}
--
Problem reports: http://cygwin.com/problems.html
FAQ: http://cygwin.com/faq/
Documentation: http://cygwin.com/docs.html
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
next prev parent reply other threads:[~2015-03-25 22:48 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-24 8:07 David Stacey
2015-03-24 18:50 ` David Stacey
2015-03-25 9:17 ` Corinna Vinschen
2015-03-25 17:10 ` Warren Young
2015-03-25 22:42 ` David Stacey
2015-03-25 23:28 ` David Stacey [this message]
2015-03-25 22:48 ` David Stacey
2015-03-30 11:04 ` Corinna Vinschen
2015-03-30 19:17 ` David Stacey
2015-03-30 23:02 ` Andrey Repin
2015-03-31 0:50 ` David Stacey
2015-03-31 3:26 ` Andrey Repin
2015-03-31 9:05 ` Achim Gratz
2015-03-31 10:04 ` Corinna Vinschen
2015-03-31 9:07 ` Corinna Vinschen
2015-03-31 18:00 ` David Stacey
2015-04-09 8:15 ` David Stacey
2015-04-09 17:24 ` Corinna Vinschen
2015-04-11 18:51 ` David Stacey
2015-04-09 21:32 ` Larry Hall (Cygwin)
2015-04-11 19:21 ` David Stacey
2015-03-25 23:29 ` David Stacey
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=55133B41.80108@tiscali.co.uk \
--to=drstacey@tiscali.co.uk \
--cc=cygwin@cygwin.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).