[Quantlib-users] empty Handle cannot be dereferenced exception

[Jake H. <jak...@gm...>]

Hi all,
I am currently working on a pull request for class ForwardRateAgreement.
I coded a new version of the constructor:

        ForwardRateAgreement(
            const Date& valueDate,
            const Date& maturityDate,
            Position::Type type,
            Rate strikeForwardRate,
            Real notionalAmount,
            Handle<YieldTermStructure> forecastCurve,
            Natural fixingDays,
            BusinessDayConvention businessDayConvention,
            Handle<YieldTermStructure> discountCurve =
Handle<YieldTermStructure>());

The last discountCurve it is used only if provided, otherwise the
forecastCurve is used also for discounting.
That's why I provided a default for it as discountCurve =
Handle<YieldTermStructure>().

Now, before submitting the PR I am trying to test some cases of the new
constructor.
Guess what? Unsurprisingly it is not working :-)
If I try to create the FRA as:

    ForwardRateAgreement FRA3(valueDate,
                              maturityDate,
                              fraFwdType,
                              strikeForwardRate,
                              fraNotional,
                              flatForwardTS,
                              fixingDays,
                              businessDayConvention);

I am getting an exception in handle.hpp which is saying "empty Handle
cannot be dereferenced". Here is the piece of code issuing the exception:
    template <class T>
    inline const ext::shared_ptr<T>& Handle<T>::operator->() const {
        QL_REQUIRE(!empty(), "empty Handle cannot be dereferenced");
        return link_->currentLink();

I am getting the same exception even if I call the new constructor by
passing explicitly the empty discount curve:

    ForwardRateAgreement FRA3(valueDate,
                              maturityDate,
                              fraFwdType,
                              strikeForwardRate,
                              fraNotional,
                              flatForwardTS,
                              fixingDays,
                              businessDayConvention,
                              Handle<YieldTermStructure>());

What am I missing? Thanks in advance for your help.