ancient TAGS references to deleted files remain in memory

ancient TAGS references to deleted files remain in memory

[Benjamin Rutt]

I rebuild my TAGS files often (like 3 times per hour) via

    find /some/projectdir -name "*.c" -o "*.cpp" -o "*.h"

I have two of these files in tags-table-list.  By updating TAGS files
often, new methods, variables, etc. that I add in my code are
frequently picked up automatically by the time I want to visit them
with M-. or M-x tags-search.

However, sometimes, I delete files from my project directories, yet
the TAGS file must still somehow contain some entries in memory that
reference these deleted files.  I get errors like the following during
M-x tags-search:

Opening input file: no such file or directory, /some/projectdir/STORM/quality/system/stormtestbinaryds.cpp

where the mentioned filename is one I had deleted.

I know I can restart my emacs to get rid of these warnings, but I like
to leave emacs running for at least a week if not a month.  I've also
tried M-x tags-reset-tags-tables followed by M-x visit-tags-table to a
newly built TAGS file but that doesn't help either.  Is there any
other solution to this problem other than restarting emacs?
-- 
Benjamin Rutt

Re: ancient TAGS references to deleted files remain in memory

[Benjamin Rutt]

Benjamin Rutt <rutt.4+news@osu.edu> writes:

> I rebuild my TAGS files often (like 3 times per hour) via
>
>     find /some/projectdir -name "*.c" -o "*.cpp" -o "*.h"
>
> I have two of these files in tags-table-list.  By updating TAGS files
> often, new methods, variables, etc. that I add in my code are
> frequently picked up automatically by the time I want to visit them
> with M-. or M-x tags-search.
>
> However, sometimes, I delete files from my project directories, yet
> the TAGS file must still somehow contain some entries in memory that
> reference these deleted files.  I get errors like the following during
> M-x tags-search:
>
> Opening input file: no such file or directory, /some/projectdir/STORM/quality/system/stormtestbinaryds.cpp
>
> where the mentioned filename is one I had deleted.

FYI, I'm fixing this for now by killing all TAGS buffers before M-x
tags-search is called:

;; for now, fix bug of files disappearing from TAGS files messing up
;; M-x tags-search.  in the future, fix the logic in
;; `tags-verify-table' to detect files being removed.  The problem is
;; that in the TAGS buffers, the buffer-local variable
;; `tags-table-files' is out of date.
(defadvice tags-search (before kill-TAGS-buffers activate)
  (let ((active-TAGS-bufs
	 (delq nil
	       (mapcar
		(lambda (x)
		  (if (string-match "TAGS$" (buffer-name x)) x nil))
		(buffer-list)))))
    (mapc
     (lambda (x)
       (kill-buffer x))
     active-TAGS-bufs)))

When I have more time, I'll look at a better solution, maybe a patch
to etags.el is needed.
-- 
Benjamin Rutt