Subject: bug#35767: 26.1; byte compiler lost warning about calling define-key with wrong number of arguments

From: Alex Branham <[email-masked]>
Date: Thu, 16 May 2019 16:24:21 -0500

Save a file with this line somewhere and call it foo.el:

(define-key "l" #'ignore)

Then call:

emacs -Q --eval "(setq byte-compile-error-on-warn t)" -batch -f batch-byte-compile foo.el

it _should_ emit an error since define-key gets called with the wrong
number of arguments. In Emacs 25.3, it does. In Emacs 26.1 and Emacs
built recently from git master, it does not.

Alex