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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Noah Misch <noah@leadboat.com>
cc: pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Prevent concurrent SimpleLruTruncate() for any given SLRU.
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Comments: In-reply-to Noah Misch <noah@leadboat.com>
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Noah Misch <noah@leadboat.com> writes:
> Prevent concurrent SimpleLruTruncate() for any given SLRU.

I find it fairly scary that you've changed enum LockTagType in the
back branches.  Are we quite certain that no extensions have compiled-in
values of that enum?

Safer from an ABI standpoint would be to add the new value at the end,
at least in the back branches.

			regards, tom lane