bytecount too large (> 1Gb) when adding HypoTestInverterResult

Hi,

I and have been trying to add multiple 'RooStats::HypoTestInverterResult' objects using the Add command (https://root.cern.ch/doc/master/classRooStats_1_1HypoTestInverterResult.html#a930d8cded51f8609654bb37b2b67f6d6)

It seems that when combining many HypoTestInverterResult objects, the object is exceeding the TBuffer limit of 1 Gb, as I get the error :

"Error in <TBufferFile::WriteByteCount>: bytecount too large (more than 1073741822)"

Additionally, when combining a fewer number of HypoTestInverterResult objects, the size of the combined file is the exact sum of the size components, which I assume is not intended behaviour?

This problem seems to be relating to the number of toys being added together, so we suspect that RooStats trying to call the properties of each toy.

This problem has been tested in versions 6.18.04 and 6.20.02. 

Thanks,

Adam