Re: [PATCH v3 7/9] Makefile: document SHA-1 and SHA-256 default and selection order

> For the *_SHA1 and *_SHA256 flags we've discussed the various flags,
> but not the fact that when you define multiple flags we'll pick one.
>
> Which one we pick depends on the order they're listed in the Makefile,
> which differed from the order we discussed them in this documentation.
>
> Let's be explicit about how we select these, and re-arrange the
> listings so that they're listed in the priority order we've picked.
>
> I'd personally prefer that the selection was more explicit, and that
> we'd error out if conflicting flags were provided, but per the
> discussion downhtread of[1] the consensus was to keep theses semantics.
>
> This behavior make it easier to e.g. integrate with autoconf-like

> systems, where the configuration can provide everything it can
> support, and Git is tasked with picking the first one it prefers.
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
> ---
> diff --git a/Makefile b/Makefile
> @@ -481,6 +481,14 @@ include shared.mak
> +# ==== Default SHA-1 backend ====
> +#
> +# If no *_SHA1 backend is picked we'll fall fall back on using the
> +# default.