Better coverage?

I've just briefly looked at the codecov reports (many thanks for doing this @mborland !) to see what needs improving, and I'm seeing a lot of false flags, for example in https://app.codecov.io/gh/boostorg/math/pull/1067/blob/include/boost/math/special_functions/lanczos.hpp line 870 only the final initializer in the list is marked as covered, even though they must have all been executed if one has! Is there anything we can do about this?