Hello.

Starting from emacs -Q, in the *scratch* buffer type:
(let ((function 'foo))
  function)

Note that function gets the font-lock-keyword-face.  I think it shouldn't,
because it is being used as a variable.

Similarly, if you type:
(defun foo (function)
  nil)

the same happens.

It probably happens with others special forms, but function is quite
noticeable, because it is not uncommon to use it as an argument or as a
variable inside a let expression.

Best regards,
Mauro.

In GNU Emacs 27.0.50 (build 1, i686-pc-linux-gnu, GTK+ Version 3.18.9)
 of 2019-08-18 built on the-blackbeard
Repository revision: ee1c638cff27f3bcdd8936617d67f79fe07d6df1
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.11906000
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