It's often very useful to run:
 
# cp --preserve=xattr aaa.txt  bbb.txt
Running this on Guix I get:
 
cp: cannot preserve extended attributes, cp is built without xattr support
 
I.e., it's used in Yocto build system.
 
There is a workaround: https://github.com/mnd/guix-mnd-pkgs/blob/master/mnd/packages/coreutils.scm, but I believe that this should be considered as bug and fixed in upstream (like Fedora did https://bugzilla.redhat.com/show_bug.cgi?id=603359).
 
Thank you!
 
 
-- 
Best regards,
Timofey Komarov