2017-11-16 17:57 GMT+01:00 Eli Zaretskii <eliz@gnu.org>:

> > From: Fabrice Popineau <fabrice.popineau@centralesupelec.fr>
> > Date: Thu, 16 Nov 2017 17:31:40 +0100
> > Cc: Phillip Lord <phillip.lord@russet.org.uk>,
> >       Jostein Kjønigsen <jostein@kjonigsen.net>,
> >       Jostein Kjønigsen <jostein@secure.kjonigsen.net>,
> >       Drew Adams <drew.adams@oracle.com>, Emacs developers <
> emacs-devel@gnu.org>
> >
> >  > The last step takes an hour.
> >
> >  Try "make -j8" instead, and it will end much faster.
> >
> > Well, the slow part is still configure, because of the numerous
> instances of shell that are launched.
>
> Not here, it isn't.  The slow part is byte compilation of the files
> with bootstrap-emacs, until it is rebuilt with byte-compiled compiler.
>

Phillip said :

./configure ; make

Since when does it bootstrap emacs and recompile elc files ?

And on my machine, ./configure is about 10 times slower than compiling
emacs itself (the make -j8 part).