bug#14470: 24.3.50; semantic: C-c , g in Lisp files throws a cryptic error

[Jambunathan K <kjambunathan@gmail.com>]

1. Enable semantic

      (semantic-mode 1)

2. Visit some lisp file

      M-x find-library RET files RET

3. Enable debugging

      M-x toggle-debug-on-error RET

4. Start a symbol search

      C-c , g  (It doesn't seem to matter where the cursor is in the
      file.  Beginning of file is good enough.)

5. Be confronted with the following error.

Expected behaviour: Provide more informative error.  May be it should
use a user-error instead of an error.

,----
| Debugger entered--Lisp error: (wrong-type-argument syntax-table-p nil)
|   set-syntax-table(nil)
|   semantic-ctxt-current-symbol-default(nil)
|   semantic-ctxt-current-symbol()
|   semantic-ctxt-current-thing()
|   semantic-complete-default-to-tag(nil)
|   semantic-complete-read-tag-engine([object semantic-collector-project-brutish "Symrefs for: " #<buffer files.el> nil unbound unbound unbound unbound unbound #<buffer files.el>] [object semantic-displayor-traditional-with-focus-highlight "simple" nil unbound unbound] "Symrefs for: " nil nil nil)
|   semantic-complete-read-tag-project("Symrefs for: ")
|   (semantic-tag-name (semantic-complete-read-tag-project "Symrefs for: "))
|   (list (semantic-tag-name (semantic-complete-read-tag-project "Symrefs for: ")))
|   call-interactively(semantic-symref-symbol nil nil)
|   command-execute(semantic-symref-symbol)
`----



In GNU Emacs 24.3.50.3 (i686-pc-linux-gnu, GTK+ Version 2.20.1)
 of 2013-05-25 on debian-6.05
Bzr revision: 112729 monnier@iro.umontreal.ca-20130525030804-6onx9rhvib7pv3fc
Windowing system distributor `The X.Org Foundation', version 11.0.10707000
Important settings:
  value of $LANG: en_IN
  locale-coding-system: iso-latin-1-unix
  default enable-multibyte-characters: t