bug#20418: 25.0.50; eldoc error: (invalid-function nil)

[Nicolas Richard]

Recipe :

Run:
emacs -Q -f package-initialize --eval '(insert "[cl-struct-package-desc]")' -f 
backward-char

then hit SPC and wait a tiny bit (well under a second).

Result: an error.

Here's the lisp backtrace:

Debugger entered--Lisp error: (invalid-function nil)
  documentation(cl-struct-package-desc t)
  elisp--get-fnsym-args-string(cl-struct-package-desc 1)
  apply(elisp--get-fnsym-args-string (cl-struct-package-desc 1))
  elisp-eldoc-documentation-function()
  apply(elisp-eldoc-documentation-function nil)
  #[128 "\300\301\"\206\300\302\"\207" [apply 
elisp-eldoc-documentation-function #[128 "\301\302\300!\"\207" 
[eldoc-documentation-function apply default-value] 4 "\n\n(fn &rest ARGS)"] 
nil] 4 nil]()
  eldoc-print-current-symbol-info()
  #[0 "\204   \205\n\303>?\205\304 \207" [eldoc-mode global-eldoc-mode 
eldoc-documentation-function (nil ignore) eldoc-print-current-symbol-info] 2]()
  apply(#[0 "\204     \205\n\303>?\205\304 \207" [eldoc-mode 
global-eldoc-mode eldoc-documentation-function (nil ignore) 
eldoc-print-current-symbol-info] 2] nil)
  timer-event-handler([t 0 0 500000 t #[0 "\204       \205\n\303>?\205\304 
\207" [eldoc-mode global-eldoc-mode eldoc-documentation-function (nil ignore) 
eldoc-print-current-symbol-info] 2] nil idle 0])


Related to this, running :

emacs -Q -f package-initialize --eval '(describe-function (quote 
cl-struct-package-desc))'

results in a second window showing :
cl-struct-package-desc is an alias for `:quick-object-witness-check',
which is not defined.  Please make a bug report.

-- 
Nico