bug#34322: reproducibility: absolute file name in tramp.elc

[Eli Zaretskii]

> From: Michael Albinus <michael.albinus@gmx.de>
> Date: Tue, 05 Feb 2019 10:00:15 +0100
> Cc: 34322@debbugs.gnu.org
> 
> Don't know how to fix it. For the records, in the emacs-26 branch,
> tramp.elc contains
> 
> --8<---------------cut here---------------start------------->8---
> (defalias 'tramp-lookup-syntax #[257 "\301 \236A\206\f\302\303\"\207" 
> [tramp-syntax #[0 "\301\267\202\n\302\207\303\207\207" [tramp-syntax 
> #s(hash-table size 2 test eq rehash-size 1.5 rehash-threshold 0.8125 purecopy 
> t data (ftp 6 sep 8)) default separate] 2 
> ("/usr/local/src/emacs-26/lisp/net/tramp-compat.elc" . 7408)] error "Wrong 
> `tramp-syntax' %s"] 4 (#$ . 25891)])
> --8<---------------cut here---------------end--------------->8---
> 
> OTOH, in the Tramp git repository, branch tramp-2-3-stable, tramp.elc contains
> 
> --8<---------------cut here---------------start------------->8---
> (defalias 'tramp-lookup-syntax #[257 "\301\267\202 \302\202 \303\202 
> \236A\206 \304\305\"\207" [tramp-syntax #s(hash-table size 2 test eq 
> rehash-size 1.5 rehash-threshold 0.8125 purecopy t data (ftp 6 sep 10)) 
> default separate error "Wrong `tramp-syntax' %s"] 4 (#$ . 25800)])
> --8<---------------cut here---------------end--------------->8---
> 
> I have no idea where the absolute file name in the former comes
> from.

I tried to explain what it means in another message.

> Both repositories use the same Emacs 26.1.91 binary for the build.

I think whether there is or isn't such a reference depends on whether
tramp-compat.elc exists when you byte-compile tramp.c.  Try removing
the former or renaming it, and you get the contents you have in the
second excerpt.  So perhaps whether the reference exists or not
depends on the order of the compilation, and maybe also on how many
compilation jobs in parallel are run when boostrapping Emacs.