From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Petteri Hintsanen Newsgroups: gmane.emacs.help Subject: On byte compilation Date: Sun, 17 Sep 2023 21:32:32 +0300 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="16745"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:jwJUXbUKw8c06+EBfs8EqmKOXbQ= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Sun Sep 17 20:33:41 2023 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qhwaT-0004DN-H3 for geh-help-gnu-emacs@m.gmane-mx.org; Sun, 17 Sep 2023 20:33:41 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qhwZZ-0006IN-SM; Sun, 17 Sep 2023 14:32:46 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qhwZY-0006I8-J4 for help-gnu-emacs@gnu.org; Sun, 17 Sep 2023 14:32:44 -0400 Original-Received: from ciao.gmane.io ([116.202.254.214]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qhwZW-0006bg-F3 for help-gnu-emacs@gnu.org; Sun, 17 Sep 2023 14:32:44 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1qhwZS-0002m7-CI for help-gnu-emacs@gnu.org; Sun, 17 Sep 2023 20:32:38 +0200 X-Injected-Via-Gmane: http://gmane.org/ Received-SPF: pass client-ip=116.202.254.214; envelope-from=geh-help-gnu-emacs@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.help:145133 Archived-At: Hello, I'm converting some old code to use new bindat-type introduced in Emacs 28.1. I'd like to keep the legacy forms for backwards compatibility with older emacsen. But there is a problem with byte compilation. Toy example: (defconst foo-bindat-spec (eval-when-compile (if (fboundp 'bindat-type) (bindat-type ;; new form (id uint 32)) '((id u32)))) ;; legacy form "Bindat spec for foo.") What I try to accomplish here is to assign to foo-bindat-spec either the result of (bindat-type ...) or list '((id u32)), depending on whether bindat-type macro is available or not. However, Emacs' 27.2 byte compiler complains: foo.el:5:14:Warning: reference to free variable ‘uint’ even though (fboundp 'bindat-type) evaluates to nil with that Emacs version. The resulting elc seems to be ok (?) despite the warning: #@22 Bindat spec for foo. (defconst foo-bindat-spec '((id u32)) (#$ . 408)) If I relocate eval-when-compile like this (defconst foo-bindat-spec (if (eval-when-compile (fboundp 'bindat-type)) (bindat-type ;; new form (id uint 32)) '((id u32))) ;; legacy form "Bindat spec for foo.") then the byte compiler does not complain. Could someone please explain why? Thanks, Petteri