Ironseed requires working free pascal compiler; at the moment it seems there is not one available for loong64:
https://packages.debian.org/sid/fp-utils-3.2.2 so unfortunately this bug is blocked until such time as FPC becomes available for loong64. You may want to open bug there to add support for loong64: https://bugs.debian.org/cgi-bin/pkgreport.cgi?src=fpc -- Opinions above are GNU-copylefted.
