Re: advice needed for multi-threading patch

[Ken Raeburn <raeburn@raeburn.org>]

On Aug 26, 2009, at 23:12, Stefan Monnier wrote:
> Emacs's stack scanning already has to check both Lisp_Object values
> (i.e. tagged pointers) and plain direct untagged pointers.  This was
> needed IIRC because even if the C code appears to hold on to
> a Lisp_Object value, the optimizer may get rid of it and only keep the
> untagged pointer.

Does that mean that GC_USE_GCPROS_AS_BEFORE doesn't work reliably?  If  
so, maybe we should get rid of it.  (Though, it appears to be the  
default.)

>> [...getting rid of struct Lisp_Symbol...]
>
> We'll cross that bridge when we get there.  I think we'll find that  
> the
> particular interface used by the function will be a very minor issue
> (the whole function will probably need to be rewritten).

Agreed.  It wasn't particularly even important to bring up, except  
that I think Tom may be looking at changing related code.

Ken