Re: master 1233bcb: Work around GC+Cairo bug

Re: master 1233bcb: Work around GC+Cairo bug

[Robert Pluim]

eggert@cs.ucla.edu (Paul Eggert) writes:

> branch: master
> commit 1233bcb0a78755ec4f3a925b84c15b1c6f715b1c
> Author: Paul Eggert <eggert@cs.ucla.edu>
> Commit: Paul Eggert <eggert@cs.ucla.edu>
>
>     Work around GC+Cairo bug
>     
>     Workaround suggested by Robert Pluim (Bug#20890#13).
>     * src/ftfont.c (ftfont_close) [USE_CAIRO]:
>     Do nothing if GC is in progress.

And whilst this reduces the frequency of the issue, of course it
doesnʼt eliminate it. Currently Iʼve deployed the following
sledgehammer, but we really need something better:

diff --git i/src/alloc.c w/src/alloc.c
index 9fdcc7306a..5be765aeab 100644
--- i/src/alloc.c
+++ w/src/alloc.c
@@ -3191,7 +3191,7 @@ cleanup_vector (struct Lisp_Vector *vector)
        {
          /* Attempt to catch subtle bugs like Bug#16140.  */
          eassert (valid_font_driver (drv));
-         drv->close ((struct font *) vector);
+         //      drv->close ((struct font *) vector);
        }
     }

Re: master 1233bcb: Work around GC+Cairo bug

[Eli Zaretskii]

> From: Robert Pluim <rpluim@gmail.com>
> Date: Wed, 04 Apr 2018 00:14:20 +0200
> Cc: Paul Eggert <eggert@cs.ucla.edu>
> 
> >     Work around GC+Cairo bug
> >     
> >     Workaround suggested by Robert Pluim (Bug#20890#13).
> >     * src/ftfont.c (ftfont_close) [USE_CAIRO]:
> >     Do nothing if GC is in progress.
> 
> And whilst this reduces the frequency of the issue, of course it
> doesnʼt eliminate it. Currently Iʼve deployed the following
> sledgehammer, but we really need something better:

Sorry, I don't understand: are you saying that you still get crashes
inside ftfont_close, after the above commit?  If so, can you please
show the backtrace?

(Let's please continue discussing this in the bug report, not here.)