Subject: Unused lexical argument warnings not optimized away in featurep 'xemacs

From: Glenn Morris <[email-masked]>
Date: Wed, 18 Sep 2013 22:51:01 -0400

Package: emacs
Version: 24.3.50
Severity: minor

Byte-compiling this:

; -*- lexical-binding: t -*-
(if (featurep 'xemacs)
  (defun foo (blah)
   ))

gives:

foo.el:2:1:Warning: Unused lexical argument `blah'

I thought code inside "(if (featurep 'xemacs)" was supposed to be
optimized away by the compiler?