Re: limit native compilation - how

[Andy Moreton <andrewjmoreton@gmail.com>]

On Sun 16 Jan 2022, H. Dieter Wilhelm wrote:

> Eli Zaretskii <eliz@gnu.org> writes:
>
>>> From: "H. Dieter Wilhelm" <dieter@duenenhof-wilhelm.de>
>>> Cc: help-gnu-emacs@gnu.org
>>> Date: Sun, 16 Jan 2022 13:01:37 +0100
>>> 
>>> Could the difference in size result from opening my Emacs, I think I
>>> checked Emacs-28.0.91 on the machine 106MB?  On machine 55MB I didn't
>>> run Emacs yet.
>>
>> The contents of the native-lisp/ directory doesn't change once Emacs
>> is built.
>
> Really, please see below, could it be you meant perhaps the preloaded/
> folder? (Just guessing.)
>
>> If you cannot figure this out, compare the contents of the two
>> native-lisp/ directories.
>
> machine 105 MB:
> |- native-lisp/
>    |- 28.0.91-59ee6325/
>    |  |- Some .eln files
>    |  |- preloaded/
>    |     | 45 MB .eln
>    |- 28.0.91-aa40abb8/
>       | Some other .eln files
>       |- preloaded/
>          |- 45 Mb .eln files

This shows native builds for two emacs versions with different native
compilation hash signatures (which are used to ensure that the .eln
DLLs are compatible with the emacs executable that they are loaded
into).

The variable `comp-native-version-dir' contains the matching name for a
running emacs with native comilation support.

> machine 55 MB:
> |- native-lisp/
>    |- 28.0.91-59ee6325/
>    |- Some .eln files
>       |- preloaded/
>          | 45 MB .eln files
>
> Might the differences come from multiple compilations?

Yes.

    AndyM