Fixed long standing bug that testing did not reveal.
Fixed long standing bug that testing did not reveal.

gssiyankai/RoaringBitmap,RoaringBitmap/RoaringBitmap,okrische/RoaringBitmap,lemire/RoaringBitmap,gssiyankai/RoaringBitmap,RoaringBitmap/RoaringBitmap,RoaringBitmap/RoaringBitmap,gssiyankai/RoaringBitmap,RoaringBitmap/RoaringBitmap,lemire/RoaringBitmap,okrische/RoaringBitmap,lemire/RoaringBitmap,lemire/RoaringBitmap,okrische/RoaringBitmap