code: @SuppressWarnings("PMD.CompareObjectsWithEquals")
      private void processArithmetic() {
          if (stack.getStackDepth() > 1) {
              OpcodeStack.Item arg1 = stack.getStackItem(0);
              OpcodeStack.Item arg2 = stack.getStackItem(1);
  
              Units u1 = (Units) arg1.getUserValue();
              Units u2 = (Units) arg2.getUserValue();
  
              if ((u1 != null) && (u2 != null) && (u1 != u2)) {
                  bugReporter.reportBug(new BugInstance(this, BugType.CTU_CONFLICTING_TIME_UNITS.name(), NORMAL_PRIORITY).addClass(this).addMethod(this)
                          .addSourceLine(this).addString(u1.toString()).addString(u2.toString()));
              }
          }
      }
docs: false positive; we're comparing enums