Subject: Re: bug#44631: 28.0.50; Byte compilation fails if destination file is a mount point

From: Lars Ingebrigtsen <[email-masked]>
Date: Sun, 13 Dec 2020 13:32:37 +0100

Philipp Stephani <[email-masked]> writes:

> I guess it also depends on what the semantics are that
> byte-compile-file guarantees. If it attempts to guarantee atomicity,
> then only a intra-filesystem rename (or similar alternatives such as
> O_TMPFILE + linkat) are acceptable, and technically, not even the
> current fallback on EXDEV (which makes rename-file nonatomic) is OK.
> If atomic writes are best-effort, then we could always fall back to
> copy-file + delete-file on any file-error.

It's definitely best-effort, so altering byte-compile-file to try 
copy-file + delete-file sounds like the best solution to me.

-- 
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   bloggy blog: http://lars.ingebrigtsen.no