aosp h8314 build failure

console.log

Running:  avbtool add_hashtree_footer --partition_size 4227858432 --partition_name system --image out/target/product/apollo/obj/PACKAGING/systemimage_intermediates/system.img --setup_as_rootfs_from_kernel
Traceback (most recent call last):
  File "out/host/linux-x86/bin/avbtool", line 3931, in <module>
    tool.run(sys.argv)
  File "out/host/linux-x86/bin/avbtool", line 3797, in run
    args.func(args)
  File "out/host/linux-x86/bin/avbtool", line 3883, in add_hashtree_footer
    args.print_required_libavb_version)
  File "out/host/linux-x86/bin/avbtool", line 3084, in add_hashtree_footer
    fec_data = generate_fec_data(image_filename, fec_num_roots)
  File "out/host/linux-x86/bin/avbtool", line 3340, in generate_fec_data
    stderr=open(os.devnull))
  File "/usr/lib/python2.7/subprocess.py", line 190, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['fec', '--encode', '--roots', '2', 'out/target/product/apollo/obj/PACKAGING/systemimage_intermediates/system.img', '/tmp/tmp0VTBHk']' returned non-zero exit status -6
Out of space? the tree size of out/target/product/apollo/system is (MB):
945	out/target/product/apollo/system
The max is 4032 MB.
ninja: build stopped: subcommand failed.
00:48:07 ninja failed with: exit status 1