From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.bugs Subject: bug#6740: Spurious byte compiler warnings Date: Tue, 27 Jul 2010 23:40:50 +0200 Message-ID: References: <20100727200619.GC2280@muc.de> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: dough.gmane.org 1280268471 29197 80.91.229.12 (27 Jul 2010 22:07:51 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Tue, 27 Jul 2010 22:07:51 +0000 (UTC) Cc: 6740@debbugs.gnu.org To: Dan Nicolaescu Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Wed Jul 28 00:07:49 2010 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1OdsJQ-00030C-M1 for geb-bug-gnu-emacs@m.gmane.org; Wed, 28 Jul 2010 00:07:48 +0200 Original-Received: from localhost ([127.0.0.1]:60498 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OdsJQ-0005Ax-2U for geb-bug-gnu-emacs@m.gmane.org; Tue, 27 Jul 2010 18:07:48 -0400 Original-Received: from [140.186.70.92] (port=41190 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OdsJJ-0005Ai-4E for bug-gnu-emacs@gnu.org; Tue, 27 Jul 2010 18:07:41 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OdsJI-0005Xs-2Y for bug-gnu-emacs@gnu.org; Tue, 27 Jul 2010 18:07:41 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:44869) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OdsJI-0005Xi-0O for bug-gnu-emacs@gnu.org; Tue, 27 Jul 2010 18:07:40 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.69) (envelope-from ) id 1OdrtW-00017J-14; Tue, 27 Jul 2010 17:41:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Monnier Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-To: owner@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 27 Jul 2010 21:41:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 6740 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 6740-submit@debbugs.gnu.org id=B6740.12802668444284 (code B ref 6740); Tue, 27 Jul 2010 21:41:01 +0000 Original-Received: (at 6740) by debbugs.gnu.org; 27 Jul 2010 21:40:44 +0000 Original-Received: from localhost ([127.0.0.1] helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OdrtE-000173-Go for submit@debbugs.gnu.org; Tue, 27 Jul 2010 17:40:44 -0400 Original-Received: from impaqm2.telefonica.net ([213.4.138.2]) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OdrtC-00016y-Nf for 6740@debbugs.gnu.org; Tue, 27 Jul 2010 17:40:43 -0400 Original-Received: from IMPmailhost5.adm.correo ([10.20.102.126]) by IMPaqm2.telefonica.net with bizsmtp id n3kl1e01j2jdgqJ3M9grQP; Tue, 27 Jul 2010 23:40:51 +0200 Original-Received: from ceviche.home ([83.61.51.16]) by IMPmailhost5.adm.correo with BIZ IMP id n9gq1e0060LyJBX1l9gqwB; Tue, 27 Jul 2010 23:40:51 +0200 X-Brightmail-Tracker: AAAAAA== X-TE-authinfo: authemail="monnier$movistar.es" |auth_email="monnier@movistar.es" X-TE-AcuTerraCos: auth_cuTerraCos="cosuitnetc01" Original-Received: by ceviche.home (Postfix, from userid 20848) id 45E21660BB; Tue, 27 Jul 2010 23:40:50 +0200 (CEST) In-Reply-To: (Dan Nicolaescu's message of "Tue, 27 Jul 2010 16:26:03 -0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (gnu/linux) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.11 Precedence: list Resent-Date: Tue, 27 Jul 2010 17:41:02 -0400 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:38998 Archived-At: >> Warning: value returned from (featurep (quote cc-fix)) is unused >> Warning: value returned from (featurep (quote cc-fix)) is unused >> >> It is obvious that that value is indeed used. This is a bug. > The byte compiler knows that (featurep 'xemacs) is false, so > (and (not (featurep 'cc-fix)) ... ) > will be false, so the featurep result is indeed unused. > If you use (and (featurep 'xemacs) (not (featurep 'cc-fix) ... > the warning will go away. It's one of those cases where the warning is the result of a check done "too late" (i.e. after some optimization), which means the check is not performed on the code the user sees, but on some massaged version of it. It's difficult to avoid them, short of removing all "code improvement" warnings. Stefan