Update Evaluator.scala

viperproject · Jul 15, 2023 · eb6130e · eb6130e
1 parent 4d7e88f
commit eb6130e
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/main/scala/rules/Evaluator.scala b/src/main/scala/rules/Evaluator.scala
@@ -214,7 +214,7 @@ object evaluator extends EvaluationRules {
       case pa: ast.PredicateAccess if Verifier.config.maskHeapMode() && s.qpPredicates.contains(pa.res(s.program).asInstanceOf[ast.Predicate]) =>
         val pvef: ast.Exp => PartialVerificationError = _ => pve
         evals(s, pa.args, pvef, v)((s1, tArgs, v1) => {
-          val resChunk = s.h.values.find(c => c.asInstanceOf[MaskHeapChunk].resource == pa.res(s.program)).get.asInstanceOf[BasicMaskHeapChunk]
+          val resChunk = s.h.values.find(c => c.isInstanceOf[MaskHeapChunk] && c.asInstanceOf[MaskHeapChunk].resource == pa.res(s.program)).get.asInstanceOf[BasicMaskHeapChunk]
           val ve = pve dueTo InsufficientPermission(pa)
           val maskValue = HeapLookup(resChunk.mask, toSnapTree(tArgs))
           v1.decider.assert(perms.IsPositive(maskValue)) {