Re: Soot typing failure

[Etienne Gagnon <gagnon.etienne_m@uqam.ca>]

Ondrej Lhotak wrote:
> > public class test
> > {
> >     public void main() {
> >         if (null instanceof String)
> >             System.out.println("is String");
> >         else
> >             System.out.println("is not String");
> >     }
> > }
> >
> > The code in ConstraintChecker generally assumes that expressions are of 
> > locals, however, in the above case, that is
> > obviously not true.


The constraint checker "Is Right(TM)".  Your problem is probably that typing
is applied after some optimizations.  IT SHOULD NOT.  I DISAGREE with the proposed
patch that Ondrej happily applied.


The code above should look like:

  loc_1 = null
  loc_2 = loc_1 instanceof String
  if (loc_2 != true) goto label_1
  loc_3 = "is String"
  loc4 = getstatic System.out
  loc4.invokevirtual println(loc_3)
  goto label_2
label_1:
  loc_5 = "is not String"
  loc_6 = getstatic System.out
  loc6.invokevirtual println(loc_5)
label_2:
  ...


Now, for this, the typing algorithm should yield the following assignment:

null_type  loc_1
boolean    loc_2
j.l.String loc_3
j.i.POS    loc_4
j.l.String loc_5
j.i.POS    loc_6

Or am I missing something?

Please send me the full "untyped jimple" source on which the typing algo
is applied, for each of the failing examples.  Thanks.

Etienne

--
Etienne M. Gagnon, Ph.D.             http://www.info.uqam.ca/~egagnon/
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