Exclude error types from contradictory-type-check query

smowton · smowton · commit 903e4f59f0fd · 2024-02-29T14:59:46.000Z
diff --git a/java/ql/src/Likely Bugs/Likely Typos/ContradictoryTypeChecks.ql b/java/ql/src/Likely Bugs/Likely Typos/ContradictoryTypeChecks.ql
@@ -40,7 +40,9 @@ predicate contradictoryTypeCheck(Expr e, Variable v, RefType t, RefType sup, Exp
     requiresInstanceOf(e, ssa.getAUse(), t) and
     sup = t.getAnAncestor() and
     instanceOfCheck(cond, ssa.getAUse(), sup) and
-    cond.(Guard).controls(e.getBasicBlock(), false)
+    cond.(Guard).controls(e.getBasicBlock(), false) and
+    not t instanceof ErrorType and
+    not sup instanceof ErrorType
   )
 }
 

Original file line number	Diff line number	Diff line change
`@@ -40,7 +40,9 @@ predicate contradictoryTypeCheck(Expr e, Variable v, RefType t, RefType sup, Exp`
`40`	`40`	`requiresInstanceOf(e, ssa.getAUse(), t) and`
`41`	`41`	`sup = t.getAnAncestor() and`
`42`	`42`	`instanceOfCheck(cond, ssa.getAUse(), sup) and`
`43`		`- cond.(Guard).controls(e.getBasicBlock(), false)`
	`43`	`+ cond.(Guard).controls(e.getBasicBlock(), false) and`
	`44`	`+ not t instanceof ErrorType and`
	`45`	`+ not sup instanceof ErrorType`
`44`	`46`	`)`
`45`	`47`	`}`
`46`	`48`