Subject: bug#48117: 28.0.50; Update of loaddefs.el during normal build is unreliable

From: Eli Zaretskii <[email-masked]>
Date: Fri, 30 Apr 2021 22:10:15 +0300

> Date: Fri, 30 Apr 2021 19:08:48 +0000
> From: Gregory Heytings <[email-masked]>
> cc: [email-masked]
> 
> Note that, as I said, this won't work without keeping ldefs-boot.el up to 
> date.

We (read: Glenn) already do.  You can see that in "git log".