All my amd64 problems appear to be KSE

[Marcel Moolenaar]

On Sat, Jun 05, 2004 at 03:21:29PM -0400, Daniel Eischen wrote:
> > 
> > I suppose it is really libreadline at fault here and it should check
> > SA_SIGINFO.  Do you think there might be others that don't check either?
> 
> I don't know; perhaps.
> 
> > Why doesn't this show an issue in i386?  Is it just luck that info has
> > been null and not caused a bad dereference?
> 
> When I write signal handlers, I usually check info and ucp to
> make sure they are not null before using them.  Actually, I
> rarely use them anyways so it doesn't matter if they are null
> or not.

Nevertheless, libpthread has a signal handler that takes 3 arguments
and it apparently gets called from other signal handlers (chaining)
that do not always pass along the full context; just the signal number
in this case. Consequently, info and ucp can be garbage as is the case
here. This is a general problem and potentionally causes failures on
all platforms, not just amd64. 

I tend to give blame to libreadline here, but I don't have a clear or
even complete picture of it all, so I might actually miss a vital
precondition that's being violated and that would clear libreadline...

-- 
 Marcel Moolenaar	  USPA: A-39004		 marcel at xcllnt.net