So xdelta3 is not backwards compatible with xdelta1 patches, and the xdelta1 library is proving to be quite obnoxious to add. If anyone else wants to contribute a fix, contact me for write access. I've traced it back as far as I could to serializeio_unserialize_generic_internal in generic.c of libedsio, possibly serializeio_find_entry (type) within that function. I can't interpret what is supposed to be happening there, but it isn't working.
So xdelta3 is not backwards compatible with xdelta1 patches, and the xdelta1 library is proving to be quite obnoxious to add. If anyone else wants to contribute a fix, contact me for write access. I've traced it back as far as I could to serializeio_unserialize_generic_internal in generic.c of libedsio, possibly serializeio_find_entry (type) within that function. I can't interpret what is supposed to be happening there, but it isn't working.