$ git diff-tree -c --abbrev master
176b998f5d647cbd77a9d8acf4531e930754d16d
::100644 100644 100644 cead32e... 7289e35... 992913c... MM dir/sub
::100644 100644 100644 b414108... f4615da... 10a8a9f... MM file0
$