bug#11489: 24.0.96; empty .dir-locals.el (or with comments only) gives "Error: (end-of-file)" during opening of arbitrary files

[Albert]

This bug report will be sent to the Bug-GNU-Emacs mailing list
and the GNU bug tracker at debbugs.gnu.org.  Please check that
the From: line contains a valid email address.  After a delay of up
to one day, you should receive an acknowledgement at that address.

Please write in English if possible, as the Emacs maintainers
usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and
the precise symptoms of the bug.  If you can, give a recipe
starting from `emacs -Q':

0. go to a directory of choice without an .dir-locals.el
1. make an empty file .dir-locals.el
2. open an arbitrary file, e.g. test.txt
3. In minibuffer shows: Error: (end-of-file)

I am not sure it can be prevented, but it took me quite some time
to find the reason for this error. I therefore wonder whether something
could be done to make it easier to discover something like this.
(I didn't get an automatic acknowledgement of receipt, so I sent this
report again, if it was rejected on purpose please tell me)

Further information:
It also shows up during export of org-files etc. So it took some time to find
the reason, because I was looking in the wrong direction. I did not have
an empty .dir-locals.el, but I had commented out everything in it.

I wonder whether it would be possible to have either no error when
there is no content, or have a more specific error message that states
where no content was found.

Thanks,
Albert.

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
   `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
d:/albert/gnu/emacs/emacs-24.0.96/etc/DEBUG.


In GNU Emacs 24.0.96.1 (i386-mingw-nt5.1.2600)
 of 2012-04-29 on MARVIN
Windowing system distributor `Microsoft Corp.', version 5.1.2600
Configured using:
 `configure --with-gcc (4.6) --no-opt --enable-checking --cflags
 -ID:/devel/emacs/libs/libXpm-3.5.8/include
 -ID:/devel/emacs/libs/libXpm-3.5.8/src
 -ID:/devel/emacs/libs/libpng-dev_1.4.3-1/include
 -ID:/devel/emacs/libs/zlib-dev_1.2.5-2/include
 -ID:/devel/emacs/libs/giflib-4.1.4-1/include
 -ID:/devel/emacs/libs/jpeg-6b-4/include
 -ID:/devel/emacs/libs/tiff-3.8.2-1/include
 -ID:/devel/emacs/libs/gnutls-3.0.9/include'

Important settings:
 value of $LC_ALL: nil
 value of $LC_COLLATE: nil
 value of $LC_CTYPE: nil
 value of $LC_MESSAGES: nil
 value of $LC_MONETARY: nil
 value of $LC_NUMERIC: nil
 value of $LC_TIME: nil
 value of $LANG: ENG
 value of $XMODIFIERS: nil
 locale-coding-system: cp1252
 default enable-multibyte-characters: t

Major mode: Org

Minor modes in effect:
 tooltip-mode: t
 mouse-wheel-mode: t
 tool-bar-mode: t
 menu-bar-mode: t
 file-name-shadow-mode: t
 global-font-lock-mode: t
 font-lock-mode: t
 blink-cursor-mode: t
 auto-composition-mode: t
 auto-encryption-mode: t
 auto-compression-mode: t
 line-number-mode: t
 transient-mark-mode: t

Recent input:
<up> <down> <down> <up> <return> C-x k <return> C-x
C-f . d i r - l o c a l s . o r g <backspace> <backspace>
<backspace> e l <return> C-x k <return> g <home> <C-home>
g <down> <down> g <down> C-x C-f . <up> <return> C-x
s <return> C-x s y <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> C-x
k <return> g <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <up> <up> <up> <up> <up>
<up> <up> <up> <return> C-x k <return> <C-home> <down>
<down> <down> <down> <down> <down> <down> <up> <up>
<up> <return> <down> <down> <backspace> <down> <right>
<left> <right> <right> <left> <down> <down> <down>
<up> <up> <right> <left> <up> <down> <up> <right> <delete>
<delete> <delete> <delete> C-x C-s C-x k <return> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <down> <down> <down> <down> <down> <down> <down>
<down> <up> <up> <up> <up> <up> <up> <up> <up> <return>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo>
<help-echo> <help-echo> <help-echo> <help-echo> <menu-bar>
<help-menu> <send-emacs-bug-report>

Recent messages:
call-interactively: Beginning of buffer
byte-code: Beginning of buffer
byte-code: End of buffer
byte-code: Beginning of buffer
call-interactively: End of buffer
delete-forward-char: End of buffer [4 times]
Saving file d:/albert-closed/ivlos/webfolio/org/.dir-locals.el...
Wrote d:/albert-closed/ivlos/webfolio/org/.dir-locals.el
OVERVIEW
Error: (end-of-file)

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message rfc822 mml mml-sec
mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils
mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr
mail-utils org-wl org-w3m org-vm org-rmail org-mhe org-mew org-irc
org-jsinfo org-infojs org-html org-exp ob-exp org-exp-blocks find-func
org-agenda org-info org-gnus org-docview org-bibtex bibtex org-bbdb org
byte-opt warnings bytecomp byte-compile cconv macroexp advice help-fns
advice-preload ob-emacs-lisp ob-tangle ob-ref ob-lob ob-table
org-footnote org-src ob-comint ob-keys ob ob-eval org-pcomplete
pcomplete comint ansi-color ring org-list org-faces org-compat
org-entities org-macs noutline outline easy-mmode format-spec cal-menu
easymenu calendar cal-loaddefs dired-aux vc-hg dired regexp-opt
time-date tooltip ediff-hook vc-hooks lisp-float-type mwheel dos-w32
disp-table ls-lisp w32-win w32-vars tool-bar dnd fontset image fringe
lisp-mode register page menu-bar rfn-eshadow timer select scroll-bar
mouse jit-lock font-lock syntax facemenu font-core frame cham georgian
utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean
japanese hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese case-table epa-hook jka-cmpr-hook help simple abbrev
minibuffer loaddefs button faces cus-face files text-properties overlay
sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote make-network-process multi-tty emacs)