From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.devel Subject: Re: Proposed removal of struct frame->select_mini_window_flag. Date: Wed, 18 May 2022 17:03:13 +0000 Message-ID: References: <83pmkaertm.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="31301"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Wed May 18 19:05:57 2022 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 1nrN7V-0007sB-IO for ged-emacs-devel@m.gmane-mx.org; Wed, 18 May 2022 19:05:57 +0200 Original-Received: from localhost ([::1]:42274 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nrN7U-0002KP-3N for ged-emacs-devel@m.gmane-mx.org; Wed, 18 May 2022 13:05:56 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:57990) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nrN4w-0001K6-LR for emacs-devel@gnu.org; Wed, 18 May 2022 13:03:19 -0400 Original-Received: from colin.muc.de ([193.149.48.1]:12270 helo=mail.muc.de) by eggs.gnu.org with smtp (Exim 4.90_1) (envelope-from ) id 1nrN4u-0002oj-DK for emacs-devel@gnu.org; Wed, 18 May 2022 13:03:18 -0400 Original-Received: (qmail 31791 invoked by uid 3782); 18 May 2022 17:03:14 -0000 Original-Received: from acm.muc.de (p4fe15a4c.dip0.t-ipconnect.de [79.225.90.76]) (using STARTTLS) by colin.muc.de (tmda-ofmipd) with ESMTP; Wed, 18 May 2022 19:03:13 +0200 Original-Received: (qmail 19943 invoked by uid 1000); 18 May 2022 17:03:13 -0000 Content-Disposition: inline In-Reply-To: <83pmkaertm.fsf@gnu.org> X-Submission-Agent: TMDA/1.3.x (Ph3nix) X-Primary-Address: acm@muc.de Received-SPF: pass client-ip=193.149.48.1; envelope-from=acm@muc.de; helo=mail.muc.de X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable 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" Xref: news.gmane.io gmane.emacs.devel:289926 Archived-At: Hello, Eli. On Wed, May 18, 2022 at 19:19:49 +0300, Eli Zaretskii wrote: > > Date: Wed, 18 May 2022 15:56:28 +0000 > > From: Alan Mackenzie > > I came across struct frame->select_mini_window_flag while looking at bug > > #55414. > > More accurately, my attention was diverted for over an hour, trying to > > work out how this boolean could be maintained in a consistent state, > > given that it gets splatted to false every time Fselect_window gets > > called. > > Then it dawned on me that the variable has no function - if the > > mini-window is the selected window, this is fully represented by struct > > frame->selected_window's value. > > So, I propose to remove this variable and all its "uses". Does anybody > > object? > I don't think I follow. Did you see this fragment in frame.c: > sf->select_mini_window_flag = MINI_WINDOW_P (XWINDOW (sf->selected_window)); > selected_frame = frame; > move_minibuffers_onto_frame (sf, for_deletion); > if (f->select_mini_window_flag > && !NILP (Fminibufferp (XWINDOW (f->minibuffer_window)->contents, Qt))) > f->selected_window = f->minibuffer_window; Yes, I saw it. > How will this logic work without that flag? There is no logic which uses it. These lines in frame.c set the flag in sf (the old frame), and test it in f (the new frame). It is intended to be a durable flag saying whether or not the mini-window in a non-selected frame is to be selected at the next do_switch_frame () into it. This might make sense if there were something setting f->selected_window without going through the proper functions. But there isn't, apart from in an initialisation of a new struct frame in xdisp.c. What we do have is the setting of the flag unconditionally to false in select_window (window.c), with no attempt being made to save and restore the current value. Considering that Fselect_window can be called from gui_consider_frame_title (xdisp.c) during a redisplay (with the current bug fix), this means the flag can be initialised to false asynchronously at any time. This is strong evidence that it is not really used. -- Alan Mackenzie (Nuremberg, Germany).