GNU bug report logs - #48181
incremental autoloads update can put output in wrong file

Previous Next

Full log

View this message in rfc822 format

From: Glenn Morris <rgm <at> gnu.org>
To: 48181 <at> debbugs.gnu.org
Cc: Stefan Monnier <monnier <at> iro.umontreal.ca>
Subject: bug#48181: incremental autoloads update can put output in wrong file
Date: Sun, 02 May 2021 21:08:57 -0400

Package: emacs
Version: 28.0.50

I tried to figure out exactly why 68bf917896 caused non-bootstrap builds
to fail, because IIUC in theory it shouldn't have. I think this is why:

1) before 68bf917896, lisp/loaddefs.el contains sections like this:

  ;;;### (autoloads nil "texnfo-upd" "textmodes/texnfo-upd.el" (0 0
  ;;;;;;  0 0))
  ;;; Generated autoloads from textmodes/texnfo-upd.el

  (register-definition-prefixes "texnfo-upd" '("texinfo-"))

So even though there aren't any real autoloads in texnfo-upd.el, it's
not in the "no autoloads" section.

2) 68bf917896 added real autoload cookies to texnfo-upd.el, and set
generated-autoload-file to texinfo-loaddefs.el.

3) make-directory-autoloads correctly finds that texnfo-upd.el is newer
than loaddefs.el, so we execute this branch:
  
  (t
   (setq changed t)
   (autoload-remove-section (match-beginning 0))
   (if (autoload-generate-file-autoloads
         ;; Passing `current-buffer' makes it insert at point.   
         file (current-buffer) buffer-file-name)
        (push file no-autoloads)))

Because a non-nil OUTBUF is passed to autoload-generate-file-autoloads,
it ignores the buffer-local setting for generated-autoload-file,
and so puts the autoloads in the main loaddefs.el file, which is wrong.


In contrast, if the input loaddefs.el file in step 1 had texnfo-upd.el
in the "no loaddefs" section, then we would execute this branch:

  ;; Passing nil as second argument forces                             
  ;; autoload-generate-file-autoloads to look for the right            
  ;; spot where to insert each autoloads section.                      
  ((setq file-time
         (autoload-generate-file-autoloads file nil buffer-file-name))
 
As the comment says, this version has OUTBUF nil, so the loaddefs end up
the right file.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.