Testing whether Xlib threading support works in XORG-RELEASE-1 branch...

[Jim Gettys]

Roland,

While I don't doubt there could be problems, you should
be aware in the past that Mozilla's threading itself was badly
broken (IIRC, at the time wasn't even actually calling Xlib's thread
initialization at all; this was in late Netscape days).  I
remember a very frustrating debugging session on the
phone with Keithp where we ended up having to conclude we
couldn't fix it (it being Netscape, without source available),
and that the fault was 100% Netscape's.

So before going down this (potential) rat-hole, what makes
you believe that the tests themselves are not buggy?  Chasing
threading bugs through mozilla isn't something we'd like
to do, given its size.

Chris, do you know of any outstanding X threading
problems?  If you do, can you give us a clue as to what is
going on?
                              - Jim

On Mon, 2004-03-22 at 19:56, Roland Mainz wrote:
> Hi!
> 
> ----
> 
> Recently I added some code to the Mozilla codebase (see
> http://bugzilla.mozilla.org/show_bug.cgi?id=235188) to test whether the
> threading support in Xlib is useable or not. After the code landed I did
> some tests with the older Xorg/Xfree86 releases... with devastating
> results - _NONE_ of the tested platforms (Linux, AIX, Solaris) was able
> to run Mozilla with threading support enabled. All builds hung with a
> deadlock, usually somewhere in X extension libraries.
> 
> Therefore it would be nice to test whether Xlib and the X11 extension
> libraries and file bugs on demand if there are any problems left
> (Xfree86 people did some work on that recently... but I am not sure
> whether the fixes are "complete" to run such a complex application like
> Mozilla).
> 
> Testing the thread support with Mozilla can be done like this:
> 1. Download a Mozilla build (>= release 1.7b, see
> http://www.mozilla.org/releases/)
> % wget
> 'http://ftp.mozilla.org/pub/mozilla.org/mozilla/releases/mozilla1.7b/mozilla-i686-pc-linux-gnu-1.7b.tar.gz'
> 
> 2. Unpack it:
> % gunzip -c mozilla-i686-pc-linux-gnu-1.7b.tar.gz | tar -xf -
> 
> 3. Set the MOZILLA_X11_XINITTHREADS env variabe to "1":
> % export MOZILLA_X11_XINITTHREADS=1
> 
> 4. Run Mozilla
> % ./mozilla/mozilla
> 
> Current result:
> Mozilla hangs at startup
> 
> Expected result:
> Mozilla should run without problems, incl. the Macromedia Flash plugin
> and printing via Xprint (see http://www.mozilla.org/projects/xprint/ and
> http://xprint.mozdev.org).
> 
> ----
> 
> Bye,
> Roland
-- 
Jim Gettys <Jim.Gettys at hp.com>
HP Labs, Cambridge Research Laboratory