bug#21695: 25.0.50; Change most occurrences of `setq' in Emacs manual to `customize-set-variable'? Really?

[Gregory Heytings]

> > +       if (!EQ (plist, Qnil) && !NILP (Fplist_get (plist, Qcustom_set)))
> > +         safe_call2 (Qdisplay_warning, Qsetq,
> > +                     CALLN (Fformat,
> > +                            build_string
> > +                            ("`%s' should be set with 
> > `customize-set-variable'"),
> > +                            sym));
>
> I haven't tried the patch, but won't this be triggered by the code 
> that's handling the variables?  For instance, `latin1-display' has a 
> :set, but the file itself does `(setq latin1-display t)' etc.  (This is 
> a very common pattern.)

No, (latin1-display 'latin-2) does not raise a warning with the patch, 
because latin1-disp.el is bytecompiled, and Fsetq is not used when 
bytecompiled code is executed (bytecompiled code only uses Fset).

That being said, I would say that using (setq latin1-display t) when 
latin1-display has a :set is always a bug, in the init file, 
interactively, or in built-in code (bytecompiled or not), and that (set 
'latin1-display t) should be used instead.  WDYT?