Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
ERROR: Command failed: 
 # /usr/bin/systemd-nspawn -q -M 87dd6d35a40b42c0b5cbfb593996a862 -D /var/lib/mock/make-srpm-method/root -a -u mockbuild --drop-capability=CAP_SYS_ADMIN,CAP_IPC_OWNER,CAP_KILL,CAP_LEASE,CAP_LINUX_IMMUTABLE,CAP_NET_BIND_SERVICE,CAP_NET_BROADCAST,CAP_NET_RAW,CAP_SETGID,CAP_SETPCAP,CAP_SETUID,CAP_SYS_CHROOT,CAP_SYS_NICE,CAP_SYS_PTRACE,CAP_SYS_TTY_CONFIG,CAP_SYS_RESOURCE,CAP_SYS_BOOT,CAP_AUDIT_WRITE,CAP_AUDIT_CONTROL --bind=/tmp/mock-resolv.lozk8zao:/etc/resolv.conf --bind=/dev/btrfs-control --bind=/dev/mapper/control --bind=/dev/fuse --bind=/dev/loop-control --bind=/dev/loop0 --bind=/dev/loop1 --bind=/dev/loop2 --bind=/dev/loop3 --bind=/dev/loop4 --bind=/dev/loop5 --bind=/dev/loop6 --bind=/dev/loop7 --bind=/dev/loop8 --bind=/dev/loop9 --bind=/dev/loop10 --bind=/dev/loop11 --console=pipe --setenv=TERM=vt100 --setenv=SHELL=/bin/bash --setenv=HOME=/builddir --setenv=HOSTNAME=mock --setenv=PATH=/usr/bin:/bin:/usr/sbin:/sbin '--setenv=PROMPT_COMMAND=printf "\033]0;<mock-chroot>\007"' '--setenv=PS1=<mock-chroot> \s-\v\$ ' --setenv=LANG=C.UTF-8 --resolv-conf=off bash --login -c '/usr/bin/rpmbuild -bs  --target aarch64 --nodeps /builddir/build/SPECS/powerdevil.spec'
A sole error.