Re: [PATCH] merge-recursive: fix the fix to the diff3 common ancestor label

> This resulted in garbage strings being printed for the virtual merge
> bases, which was visible in git.git by just merging commit b744c3af07
> into commit 6d8cb22a4f.  There are two ways to fix this: set
> opt->ancestor to NULL after using it to avoid re-use, or add a
> !opt->priv->call_depth check to the if block for using a pre-defined
> opt->ancestor.  Apply both fixes.

> Signed-off-by: Elijah Newren <newren@gmail.com>
> ---
>  merge-recursive.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/merge-recursive.c b/merge-recursive.c
> index e12d91f48a..2653ba9a50 100644
> --- a/merge-recursive.c
> +++ b/merge-recursive.c
> @@ -3550,7 +3550,7 @@ static int merge_recursive_internal(struct merge_options *opt,
>  		merged_merge_bases = make_virtual_commit(opt->repo, tree,
>  							 "ancestor");
>  		ancestor_name = "empty tree";
> -	} else if (opt->ancestor) {
> +	} else if (opt->ancestor && !opt->priv->call_depth) {
>  		ancestor_name = opt->ancestor;
>  	} else if (merge_bases) {
>  		ancestor_name = "merged common ancestors";
> @@ -3600,6 +3600,7 @@ static int merge_recursive_internal(struct merge_options *opt,
>  							  merged_merge_bases),
>  				     &result_tree);
>  	strbuf_release(&merge_base_abbrev);
> +	opt->ancestor = NULL;  /* avoid accidental re-use of opt->ancestor */
>  	if (clean < 0) {
>  		flush_output(opt);
>  		return clean;