pub unsafe extern "C" fn git_merge_analysis_for_ref(
    analysis_out: *mut git_merge_analysis_t,
    pref_out: *mut git_merge_preference_t,
    repo: *mut git_repository,
    git_reference: *mut git_reference,
    their_heads: *mut *const git_annotated_commit,
    their_heads_len: usize
) -> c_int