The build was broken failing on unneccessary memsets. This issue was fixed upstream in 3.7 and discussed in https://github.com/zeroc-ice/ice/issues/82 The patch pertaining to the error causing the actual failure still applies nicely onto the 3.6 version. Hydra logs of breakage: https://hydra.nixos.org/build/100440955/nixlog/1
Rename from zeroc_ice. Take various improvements from Arch zero-ice package. Move old version to zeroc-ice-36.