C++: Use Function::hasErrors in queries

Author: calumgrant

cpp/ql/src/Best Practices/Unused Entities/UnusedLocals.ql

@@ -57,5 +57,5 @@ where
   not declarationHasSideEffects(v) and
   not exists(AsmStmt s | f = s.getEnclosingFunction()) and
   not v.getAnAttribute().getName() = "unused" and
-  not any(ErrorExpr e).getEnclosingFunction() = f // unextracted expr may use `v`
+  not f.hasErrors()
 select v, "Variable " + v.getName() + " is not used."

cpp/ql/src/Likely Bugs/Memory Management/ReturnStackAllocatedMemory.ql

@@ -29,7 +29,7 @@ class ReturnStackAllocatedMemoryConfig extends MustFlowConfiguration {
   override predicate isSource(Instruction source) {
     exists(Function func |
       // Rule out FPs caused by extraction errors.
-      not any(ErrorExpr e).getEnclosingFunction() = func and
+      not func.hasErrors() and
       not intentionallyReturnsStackPointer(func) and
       func = source.getEnclosingFunction()
     |

cpp/ql/src/Likely Bugs/Memory Management/UsingExpiredStackAddress.ql

@@ -24,7 +24,7 @@ predicate instructionHasVariable(VariableAddressInstruction vai, StackVariable v
   // Pointer-to-member types aren't properly handled in the dbscheme.
   not vai.getResultType() instanceof PointerToMemberType and
   // Rule out FPs caused by extraction errors.
-  not any(ErrorExpr e).getEnclosingFunction() = f
+  not f.hasErrors()
 }
 
 /**

cpp/ql/src/jsf/4.13 Functions/AV Rule 114.ql

@@ -49,7 +49,7 @@ predicate functionsMissingReturnStmt(Function f, ControlFlowNode blame) {
 predicate functionImperfectlyExtracted(Function f) {
   exists(CompilerError e | f.getBlock().getLocation().subsumes(e.getLocation()))
   or
-  exists(ErrorExpr ee | ee.getEnclosingFunction() = f)
+  f.hasErrors()
   or
   count(f.getType()) > 1
   or