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: New optimisations for long raw strings in C++ Mode. Date: Sun, 7 Aug 2022 16:13:56 +0000 Message-ID: References: <87r11s2p7f.fsf@gnus.org> <87fsi818ju.fsf@gnus.org> <87wnbkyuhe.fsf@gnus.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="2284"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org To: Lars Ingebrigtsen Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Aug 07 18:14:38 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 1oKivG-0000Un-6i for ged-emacs-devel@m.gmane-mx.org; Sun, 07 Aug 2022 18:14:38 +0200 Original-Received: from localhost ([::1]:49546 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oKivE-0007fi-JT for ged-emacs-devel@m.gmane-mx.org; Sun, 07 Aug 2022 12:14:36 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:47624) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oKiuf-0006zE-PR for emacs-devel@gnu.org; Sun, 07 Aug 2022 12:14:01 -0400 Original-Received: from colin.muc.de ([193.149.48.1]:32279 helo=mail.muc.de) by eggs.gnu.org with smtp (Exim 4.90_1) (envelope-from ) id 1oKiud-0007vb-Nd for emacs-devel@gnu.org; Sun, 07 Aug 2022 12:14:01 -0400 Original-Received: (qmail 47620 invoked by uid 3782); 7 Aug 2022 16:13:57 -0000 Original-Received: from acm.muc.de (p2e5d5157.dip0.t-ipconnect.de [46.93.81.87]) (using STARTTLS) by colin.muc.de (tmda-ofmipd) with ESMTP; Sun, 07 Aug 2022 18:13:56 +0200 Original-Received: (qmail 5324 invoked by uid 1000); 7 Aug 2022 16:13:56 -0000 Content-Disposition: inline In-Reply-To: <87wnbkyuhe.fsf@gnus.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=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" Xref: news.gmane.io gmane.emacs.devel:293218 Archived-At: Hello, Lars. On Sun, Aug 07, 2022 at 16:54:37 +0200, Lars Ingebrigtsen wrote: > Simplest case to reproduce: > M-: (setq long-line-threshold nil) > Go to a cc buffer containing: > char long_line[] = R"foo( > )foo" > M-: (insert (make-string 1000000 ?y)) > on the second line. This reliably hangs Emacs for me. Actually, when I try your recipe with make-string, it hangs for me, too, for quite a few minutes. Alternatively, when I do C-y, the insertion takes a little less than a second. In the (insert ) recipe, when it finally finishes, I see the following in *Messages*: Error during redisplay: (jit-lock-function 27) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 1527) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 3027) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 4527) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 6027) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 7527) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 1000027) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 9027) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 10527) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 12027) signaled (error "Stack overflow in regexp matcher") Error during redisplay: (jit-lock-function 13527) signaled (error "Stack overflow in regexp matcher") .... and so on. So it's a bug needing fixing, rather than systematic slowness. -- Alan Mackenzie (Nuremberg, Germany).