bug#4402: apropos-documentation and platform-specific docs

[Eli Zaretskii <eliz@gnu.org>]

> From: Glenn Morris <rgm@gnu.org>
> Date: Fri, 11 Sep 2009 03:01:04 -0400
> Cc: 
> 
> The problem is caused by the DOC file containing three sets of
> doc-strings for Fx-create-frame, extracted from w32fns.c, xfns.c, and
> nsfns.m.
> 
> This made me wonder, why does the DOC file in my GNU/Linux build
> contain information extracted from Nextstep and Windows files that is
> never going to be relevant? Perhaps it's so that one can in principle
> share DOC files between different builds? This doesn't seem like a big
> advantage to me. I doubt (m)any people have ever shared the DOC file
> between any of these platforms. The size of DOC is a negligible part of
> a current Emacs installation.

DOC is an architecture-independent file, so it must include the doc
strings of all symbols.

> The standard solution to this kind of thing seems to be that where
> functions/variables have multiple, platform-specific definitions, each
> should have the same, unified doc-string. This is a bit of a pain.
> 
> Only putting the relevant files into the DOC file would eliminate this
> issue.

There are other solutions, but they need some infrastructure.  See
past discussions of this issue a couple of months ago.