bug#1430: 23.0.60; global-set-key with string problem

[Martin Maechler]

Here's a small code snippet that exactly shows my problem
The example is derived from real code in our group wide  default.el :
Note that the problem persists, when I use  
'emacs-snapshot -q' :

-----------------------------------

;; Martin Maechler, ETH Zurich (2008-11-26):
;; This has worked in all versions of emacs since emacs 18.59 I think,
;; but gives an error in my emacs-snapshot 23.0.60 :

(global-set-key "\C-c-\t" (insert " |_C-c TAB_| "))
;;-> error: Key sequence C-c - TAB starts with non-prefix key C-c -

;; I do see that the equivalent alternative
(global-set-key [C-c \t] (insert " |_C-c TAB_| "))
;; *does* work, however the old style key settings
;; "\C-c ..." or "\M-.." almost all  seem to work fine, 
;; so why not the above one?

-----------------------------------



In GNU Emacs 23.0.60.1 (x86_64-pc-linux-gnu, GTK+ Version 2.12.9)
 of 2008-03-19 on yellow, modified by Debian
 (emacs-snapshot package, version 1:20080228-1ubuntu1)
Windowing system distributor `The X.Org Foundation', version 11.0.70101000
configured using `configure  '--build' 'x86_64-linux-gnu' '--host' 
'x86_64-linux-gnu' '--prefix=/usr' '--sharedstatedir=/var/lib' 
'--libexecdir=/usr/lib' '--localstatedir=/var' '--infodir=/usr/share/info' 
'--mandir=/usr/share/man' '--with-pop=yes' 
'--enable-locallisppath=/etc/emacs-snapshot:/etc/emacs:/usr/local/share/emacs/23.0.60/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/23.0.60/site-lisp:/usr/share/emacs/site-lisp:/usr/share/emacs/23.0.60/leim'
 '--with-x=yes' '--with-x-toolkit=gtk' '--enable-font-backend' 
'build_alias=x86_64-linux-gnu' 'host_alias=x86_64-linux-gnu' 'CFLAGS=-DDEBIAN 
-DSITELOAD_PURESIZE_EXTRA=5000 -g -O2' 'LDFLAGS=-g -Wl,--as-needed' 'CPPFLAGS=''

Important settings:
  value of $LC_ALL: 
  value of $LC_COLLATE: de_CH
  value of $LC_CTYPE: de_CH
  value of $LC_MESSAGES: de_CH
  value of $LC_MONETARY: en_US
  value of $LC_NUMERIC: en_US
  value of $LC_TIME: en_US
  value of $LANG: de_CH
  value of $XMODIFIERS: nil
  locale-coding-system: iso-latin-1-unix
  default-enable-multibyte-characters: t

Major mode: Emacs-Lisp

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

Recent input:
<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:
Package ess removed but not purged.  Skipping setup.
Loading /etc/emacs/site-start.d/50ess.el (source)...done
Loading /etc/emacs/site-start.d/50maxima-emacs.el (source)...done
Loading /etc/emacs/site-start.d/50psvn.el (source)...done
Loading /etc/emacs/site-start.d/50records-xemacs.el (source)...done
Loading /etc/emacs/site-start.d/50vc-svn.el (source)...done
Loading /etc/emacs-snapshot/site-start.d/50vm-init.el (source)...done
Loading /etc/emacs/site-start.d/50yacas.el (source)...done
Loading /etc/emacs/site-start.d/51debian-el.el (source)...done
For information about GNU Emacs and the GNU system, type C-h C-a.