C++: fix unbound variables

Robert Marsh · Robert Marsh · commit 24c9b8b9b14d · 2019-10-30T14:06:19.000-07:00
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/raw/internal/TranslatedCall.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/raw/internal/TranslatedCall.qll
@@ -461,7 +461,10 @@ class TranslatedSideEffect extends TranslatedElement, TTranslatedArgumentSideEff
 
   override Type getInstructionOperandType(InstructionTag tag, TypedOperandTag operandTag) {
     if hasSpecificReadSideEffect(any(Opcode::BufferReadSideEffect op))
-    then result instanceof UnknownType
+    then
+      result instanceof UnknownType and
+      tag instanceof OnlyInstructionTag and
+      operandTag instanceof SideEffectOperandTag
     else (
       tag instanceof OnlyInstructionTag and
       result = arg.getType().getUnspecifiedType().(DerivedType).getBaseType() and
