pub unsafe extern "C" fn git_commit_amend(
    id: *mut git_oid,
    commit_to_amend: *const git_commit,
    update_ref: *const c_char,
    author: *const git_signature,
    committer: *const git_signature,
    message_encoding: *const c_char,
    message: *const c_char,
    tree: *const git_tree
) -> c_int