Smalltalk - Re: OSProcess fork issue with Debian built VM

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Re: OSProcess fork issue with Debian built VM

Posted by Eliot Miranda-2 on May 18, 2017; 6:39pm
URL: https://forum.world.st/OSProcess-fork-issue-with-Debian-built-VM-tp4947326p4947584.html

Hi Max,

On Thu, May 18, 2017 at 4:32 AM, Max Leske <[hidden email]> wrote:

We managed to figure out that OSProcess works when we use gcc <= 4.8 on Debian. We are happy to use 4.8 for now, so we're good. It would of course be super cool if we could use the series 6 gcc as that will soon ship with Debian 9 (stretch) but it's probably not trivial to just move to a new compiler version (as seems evident from the fact that a minor version change can mess up compilation).

For the sake of revisiting this when we have time and can debug it can you state which version(s) you tried to use which didn't work? Also, what are the compilation flags (full gcc invocation example) for the case(s) that work and the case(s) that don't?

Debugging this can be straight-forward if one can build the two versions and execute them side-by-side to pin-point the failure. Coming with a fix may be more challenging ;-)

Thanks for your help Alistair and Eliot.

Cheers,
Max

On 18 May 2017, at 11:00, [hidden email] wrote:

On 18 May 2017, at 00:50, [hidden email] wrote:

Hi Max, Hi Alistair,

On Wed, May 17, 2017 at 1:06 AM, Alistair Grant <[hidden email] <[hidden email]>>
wrote:

On Tue, May 16, 2017 at 04:59:24PM +0200, Alistair Grant wrote:
Hi Max,

On 16 May 2017 15:40, "Max Leske" <[hidden email] <[hidden email]>> wrote:

  Hi Alistair,

      On 16 May 2017, at 15:32, vm-dev-request@lists.
squeakfoundation.org <http://squeakfoundation.org/>
      wrote:

      Hi Max,

      I can't answer your question directly, but just wondering why
you are
      using
      the itimer VM when the are known issues with external calls, and
not
      the
      heartbeat VM?

  Because of the root user issue, and also because I don't care about
that
  much at the moment. I'm still experimenting and for those
experiments it
  doesn't matter which VM I use. Thirdly, the itimer VM is the one I
get when
  I use 'curl get.pharo.org/60+vmLatest <http://get.pharo.org/60+vmLatest> | bash', which is convenient
to get
  the latest VM, and to minimise differences between the VM's we built
the
  same one. I will definitely consider using the threaded VM for
production.

      P.S. I would love to see OSProcess working in 32 bit mode.

  Well, it does work already, just not when we build the VM ourselves
:/

Interesting, I had the impression that for Pharo 6 OSProcess didn't work
in
32bits, only 64, but I'm also building my own VM. I'm away from my PC,
but
I'll try and take a look.

I'm seeing the same behaviour as you, i.e. OSProcess works in a VM
downloaded from get.pharo.org <http://get.pharo.org/>, but locks up when using the VM I
compiled.

Have you looked at the build logs and eliminated compiler version, command
line flags, etc? One important file is the config.h that is produced in
the build directory. It might be informative to compare the one configure
is producing on your systems and the one that the binary builds creates.

Thanks for the pointer. I'll look into it.

Both VMs (threaded heartbeat) are based on the same source code, i.e.:

VM: 201705022326 https://github.com/OpenSmalltalk/opensmalltalk-vm.git <https://github.com/OpenSmalltalk/opensmalltalk-vm.git> $
Date: Tue May 2 16:26:41 2017 -0700 $

I'll try and take a look at this eventually, but I'm not sure how long
that will be (several weeks away, at least).

If you figure it out, please let me know.

Thanks!
Alistair

--
_,,,^..^,,,_
best, Eliot

_,,,^..^,,,_

best, Eliot