Describe-function does not load the full function help

[Yves Baumes]

Following is an extract of the result for (describe-function
'mode-line-toggle-read-only) :


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mode-line-toggle-read-only is an interactive compiled Lisp function in
`bindings.el'.

(mode-line-toggle-read-only EVENT)

Cannot open doc string file "DOC-24.3.50.1"

[back]
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What is "DOC-24.3.50.1"?
It appears I've the issue while 'describing' other functions.
I am using the last Emacs from the trunk. The other Emacs version I have
is v24.1.1 and print "Like `toggle-read-only', for the mode-line."
instead (in the case of `mode-line-toggle-read-only').

Regards
Yves