C++: Remove FPs in cpp/wrong-type-format-argument when string type is an error

Author: calumgrant

cpp/ql/src/Likely Bugs/Format/WrongTypeFormatArguments.ql

@@ -171,6 +171,10 @@ where
   not arg.isAffectedByMacro() and
   not arg.isFromUninstantiatedTemplate(_) and
   not actual.getUnspecifiedType() instanceof ErroneousType and
+  not (
+    expected instanceof PointerType and
+    actual.getUnspecifiedType().(PointerType).getBaseType() instanceof ErroneousType
+  ) and
   not arg.(Call).mayBeFromImplicitlyDeclaredFunction()
 select arg,
   "This format specifier for type '" + expected.getName() + "' does not match the argument type '" +

cpp/ql/test/query-tests/Likely Bugs/Format/WrongTypeFormatArguments/Buildless/WrongTypeFormatArguments.expected

@@ -1,2 +1 @@
 | tests.c:7:18:7:18 | 1 | This format specifier for type 'char *' does not match the argument type 'int'. |
-| tests.c:11:18:11:20 | str | This format specifier for type 'char *' does not match the argument type '<error-type> *'. |