From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Andreas Schwab Newsgroups: gmane.emacs.devel Subject: Re: master 37889523278: Add new `swap` macro and use it Date: Sat, 06 Jan 2024 10:52:58 +0100 Message-ID: <878r52g551.fsf@linux-m68k.org> References: <170452579053.27998.16123231327386305897@vcs2.savannah.gnu.org> <20240106072311.28B8FC0034E@vcs2.savannah.gnu.org> <87plye9ahs.fsf@yahoo.com> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="20925"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Cc: Po Lu , emacs-devel@gnu.org, Paul Eggert , Eli Zaretskii To: Stefan Kangas Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sat Jan 06 10:53:56 2024 Return-path: Envelope-to: ged-emacs-devel@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 1rM3NL-0005Ex-MQ for ged-emacs-devel@m.gmane-mx.org; Sat, 06 Jan 2024 10:53:55 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rM3Md-0001kB-E5; Sat, 06 Jan 2024 04:53:11 -0500 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 1rM3Mb-0001k2-I2 for emacs-devel@gnu.org; Sat, 06 Jan 2024 04:53:09 -0500 Original-Received: from mail-out.m-online.net ([2001:a60:0:28:0:1:25:1]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rM3MZ-0006LG-Dm; Sat, 06 Jan 2024 04:53:09 -0500 Original-Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 4T6bH13k21z1sB7b; Sat, 6 Jan 2024 10:53:00 +0100 (CET) Original-Received: from localhost (dynscan1.mnet-online.de [192.168.6.68]) by mail.m-online.net (Postfix) with ESMTP id 4T6bH02ZWTz1qqlS; Sat, 6 Jan 2024 10:53:00 +0100 (CET) X-Virus-Scanned: amavis at mnet-online.de Original-Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan1.mail.m-online.net [192.168.6.68]) (amavis, port 10024) with ESMTP id FTYlia68l0qE; Sat, 6 Jan 2024 10:52:59 +0100 (CET) X-Auth-Info: p8U1OnxK3mfTZpzjOwVtGcWNpX7hJrDXzjixnxt1nRQFxJu44KF8S5TD0TMp7NKC Original-Received: from tiger.home (aftr-62-216-202-146.dynamic.mnet-online.de [62.216.202.146]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Sat, 6 Jan 2024 10:52:59 +0100 (CET) Original-Received: by tiger.home (Postfix, from userid 1000) id B070A2455D5; Sat, 6 Jan 2024 10:52:58 +0100 (CET) In-Reply-To: (Stefan Kangas's message of "Sat, 6 Jan 2024 00:50:55 -0800") X-Yow: Your CHEEKS sit like twin NECTARINES above a MOUTH that knows no BOUNDS -- Received-SPF: pass client-ip=2001:a60:0:28:0:1:25:1; envelope-from=whitebox@nefkom.net; helo=mail-out.m-online.net X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:314601 Archived-At: On Jan 06 2024, Stefan Kangas wrote: > diff --git a/src/lisp.h b/src/lisp.h > index f96932ab0c1..a9782868157 100644 > --- a/src/lisp.h > +++ b/src/lisp.h > @@ -68,8 +68,13 @@ #define max(a, b) ((a) > (b) ? (a) : (b)) > #define min(a, b) ((a) < (b) ? (a) : (b)) > > /* Swap values of a and b. */ > -#define swap(a, b) \ > - do { typeof (a) __tmp; __tmp = (a); (a) = (b); (b) = __tmp; } while (0); > +#if _GL_HAVE___TYPEOF__ > +#define swap(type, a, b) \ > + do { __typeof__ (a) __tmp; __tmp = (a); (a) = (b); (b) = __tmp; } while (0); > +#else > +#define swap(type, a, b) \ > + do { type __tmp; __tmp = (a); (a) = (b); (b) = __tmp; } while (0); > +#endif Neither of these definitions are future proof: __tmp as a reserved identifier might clash with future implementations. Moreover, the first argument can easily become out of date without notice. -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."