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Date:   Mon,  9 Oct 2023 13:59:25 -0700
In-Reply-To: <ZSQ3s3ZiRcvQIKOa@nand.local>
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Subject: Re: [RFC PATCH] Not computing changed path filter for root commits
From:   Jonathan Tan <jonathantanmy@google.com>
To:     Taylor Blau <me@ttaylorr.com>
Cc:     Jonathan Tan <jonathantanmy@google.com>,
        "=?UTF-8?q?SZEDER=20G=C3=A1bor?=" <szeder.dev@gmail.com>,
        git@vger.kernel.org
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Taylor Blau <me@ttaylorr.com> writes:
> This only happens when we return REV_TREE_NEW from a call to
> `rev_compare_tree(revs, p, commit, nth_parent)`. But we'll only get
> REV_TREE_NEW back if
> 
>     repo_get_commit_tree(the_repository, p);
> 
> returns NULL. But when we call rev_same_tree_as_empty(revs, p) in the
> REV_TREE_NEW case, we return early as follows:
> 
>     struct tree *t1 = repo_get_commit_tree(revs, p);
>     if (!t1)
>       return 0;
> 
> So we won't even consult the Bloom filter in that case, since t1 is NULL
> for the same reason as what caused rev_compare_tree() to return
> REV_TREE_NEW in the first place.
> 
> I am still dumbfounded by how we would ever get REV_TREE_NEW in the
> first place, but if we did, I think we would be OK here.
> 
> Thanks,
> Taylor

Ah, good point. Your patch in
https://lore.kernel.org/git/ZQnmTXUO94%2FQy8mq@nand.local/ looks good to
me, then.