Subject: 26.0.50; 'function' fails as variable name inside lexical-let

From: David Bremner <[email-masked]>
Date: Sat, 08 Apr 2017 13:51:39 -0300

0) Put the following elisp in a file called e.g. test.el
(eval-when-compile (require 'cl))
(defun my-fun (function)
  (lexical-let ((x 1))
    (funcall function)))

1) run "emacs -Q --batch -f batch-byte-compile test.el"

2) Observe the following unhelpful error message

In toplevel form:
test.el:2:1:Error: Wrong type argument: listp, cl--function-convert

This is minimally a behaviour change since emacs 25.1.

I tested against current master branch (hash 5f319eb3a)

In GNU Emacs 26.0.50 (build 1, x86_64-pc-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2017-04-08 built on zancas
Repository revision: c5f319eb3a2e0ad97867c8dc61bfc140333fb11d
System Description:	Debian GNU/Linux 9.0 (stretch)

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For information about GNU Emacs and the GNU system, type C-h C-a.

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Memory information:
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-- 
David Bremner                                  Professor, UNB Computer Science
[email-masked]			           
http://www.cs.unb.ca/~bremner               Cross Appointment, UNB Mathematics