Re: [ANNOUNCE] Emacs 26.1 released

[Eli Zaretskii <eliz@gnu.org>]

> Date: Thu, 31 May 2018 10:34:39 -0500 (CDT)
> From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
> cc: emacs-devel@gnu.org
> 
> Developers should be cognizant of the packages they are requiring to 
> be used.

We are -- for about 5 seconds after we modify configure.ac to require
a specific version of a certain package.  Thereafter, the required
versions are recorded in configury, and nowhere else.  For example:

  WEBKIT_REQUIRED=2.12
  WEBKIT_MODULES="webkit2gtk-4.0 >= $WEBKIT_REQUIRED"

This is quite self-explanatory, right?

The problem is to collect all these requirements, express them in
human-readable form, and then keep that up-to-date whenever the
configury changes.  That's a non-trivial manual work.

Btw, the info you are looking for is generally available on the
Internet.  I like to use http://www.linuxfromscratch.org in such
cases, in particular see

  http://www.linuxfromscratch.org/blfs/view/svn/postlfs/emacs.html

(It still doesn't show Emacs 26, but it probably will soon.)

> It would be very helpful if configure specified what it is 
> specifically looking for, and includes what it needs in the error 
> message.

It does.  In your case, it didn't find the package-config file for the
relevant version, so it only could tell you that webkit2gtk-4.0 is not
installed.  Once you install it, if its version is older than the one
required, you'd see a message saying it looked for version X.Y.Z, but
didn't find it.

> It seems that the new emacs silently quit last night while the screen 
> was locked.  I may need to retreat to the previous release (25.3).

I suggest to look in the system message log to see what happened.  If
it crashed, please consider submitting a bug report.

> Something else I notice is that when I open a file which is in a 
> Mercurial repository, the /usr/bin/hg program crashes and I get an 
> Ubuntu crash report.  The Ubuntu crash report screen does not allow me 
> to copy text from it, but the command executed which crashed starts 
> with '/usr/bin/python /usr/bin/hg log -r . -l1 -template ...'.  This 
> does not happen with emacs-25.3.  The crash is due to use of a None 
> value.  The version of Mercurial provided by this Ubuntu release is 
> 2.8.2.

Please submit a separate bug report using "M-x report-emacs-bug", and
please include in the report the relevant details, such as the hg
command issued by Emacs and the Python backtrace.

Thanks.