[m-rev.] for review: Fix compiler abort during liveness detection.

[Peter Wang]

On Mon, 9 Sep 2013 14:20:25 +1000 (EST), Julien Fischer <jfischer at opturion.com> wrote:
> 
> On Mon, 9 Sep 2013, Julien Fischer wrote:
> 
> >
> > On Mon, 9 Sep 2013, Peter Wang wrote:
> >
> >> On Mon, 9 Sep 2013 13:43:28 +1000 (EST), Julien Fischer 
> >> <jfischer at opturion.com> wrote:
> >>> 
> >>> Hi Peter,
> >>> 
> >>> On Wed, 4 Sep 2013, Peter Wang wrote:
> >>> 
> >>>> [I'm not certain of the fix]
> >>> 
> >>> Neither am I.
> >>> 
> >>> Do you know where the call to goal_info_get_post_births that is causing
> >>> the aborts is?  In particular, is it whne detect_deadness (i.e. stage 2
> >>> of of liveness analysis) is processing an if-then-else?
> >> 
> >> It happens immediately afterwards in the call to add_liveness_after_goal.
> >
> > So even sooner in fact.  I think you should go ahead and commit your
> > fix since it's an improvement on the status quo.  I suggest you change
> > the comment that you added to something like:
> >
> >    % XXX Initialize liveness-related fields, since some Other code in
> >    % this module assumes that they are initialized.

Done.

> >
> > (There are at least two spots, the call to add_liveness_after_goal
> > and also in detect_deadness_in_goal.  Presumably, another fix would be
> > to replicate the check for condition that cannot fail at all of those
> > points?)
> 
> I meant to say "the condition that cannot succeed ... " in that
> last sentence.)
> 

Presumably, but it seems like the wrong solution.

Peter