bug#48348: 27.2; buffer-stale-function is being reset by make-indirect-buffer

[Al Haji-Ali]

Hello,

I am setting `buffer-stale-function` to prevent some buffers from being 
reverted when `global-auto-revert-mode` is enabled (I am not aware of a 
different way than setting `buffer-stale-function` to achieve this). This works 
well, but I noticed that `make-indirect-buffer` (which for example org-capture 
uses) seems to reset `buffer-stale-function` to nil (in buffer.c:906).

Is this intended? I find it strange since `buffer-stale-function` is not 
buffer-local.
Also the fact that it is reset to `nil` instead of the default 
`buffer-stale--default-function` is doubly strange.


Al

--


In GNU Emacs 27.2 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, cairo 
version 1.16.0)
 of 2021-04-06 built on thinkpad
Repository revision: deef5efafb70f4b171265b896505b92b6eef24e6
Repository branch: HEAD
Windowing system distributor 'The X.Org Foundation', version 11.0.12009000
System Description: Ubuntu 20.04.2 LTS

Configured using:
 'configure --prefix=/home/abdo/.local/ --with-json --with-modules
 --with-harfbuzz --with-compress-install --with-threads
 --with-included-regex --with-zlib --with-sound=alsa --without-gconf
 --with-mailutils --with-xft --with-xml2 --with-cairo --with-gconf
 --with-xwidgets --without-toolkit-scroll-bars 'CFLAGS=-O3 -mtune=native
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  value of $XMODIFIERS: @im=ibus
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