Re: java.lang.NullPointerException when loading SSAX.scm in kawa-1.7

[Jim White <jim at pagesmiths dot com>]

Stan Pinte wrote:
> On Fri, 04 Jul 2003 16:09:27 -0700
> Jim White <jim@pagesmiths.com> wrote:
>
> > Stan Pinte wrote:
> >
> > > when loading SSAX.scm, I am getting the following:
> > >
> > > java.lang.NullPointerException
> > >        at gnu.expr.LambdaExp.allocChildClasses(LambdaExp.java:936)
> > > ...
> >
> > The problem occurs at the second "test".  If there is just one then it
> > compiles OK.
>
> any idea why? It could be great to have Kawa run the test suite without any problem!

It has something to do with this code at gnu.expr.LambdaExp(935):

   LambdaExp owner = this;
   while (owner.heapFrame == null)
      owner = owner.outerLambda();
   closureEnvType = (ClassType) owner.heapFrame.getType();

Which might need to look something like this:

   LambdaExp owner = this;
   while (owner.heapFrame == null) {
      owner = owner.outerLambda();
      if (owner == null) {
         // Do something about the heap frame situation.
      }
   }
   closureEnvType = (ClassType) owner.heapFrame.getType();

But I don't know enough about Kawa compilation to understand if this 
where the fix goes or if this is just symptomatic.  It has something to 
do with the closure situation with siblings and let forms but that's all 
Greek to me.

Per is on vacation and I'm sure he'll provide a fix as soon as he gets 
back in a few days.  If you had to make this run before then, you could 
rewrite the code to just put each test in its own lambda or something. 
A macro could do the job one way or another I'm sure.

Jim
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