From unknown Sat Jun 14 03:47:28 2025 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Mailer: MIME-tools 5.509 (Entity 5.509) Content-Type: text/plain; charset=utf-8 From: bug#44724 <44724@debbugs.gnu.org> To: bug#44724 <44724@debbugs.gnu.org> Subject: Status: Uninitialised variables in syntax.c cause trouble. Reply-To: bug#44724 <44724@debbugs.gnu.org> Date: Sat, 14 Jun 2025 10:47:28 +0000 retitle 44724 Uninitialised variables in syntax.c cause trouble. reassign 44724 emacs submitter 44724 Alan Mackenzie severity 44724 normal tag 44724 notabug thanks From debbugs-submit-bounces@debbugs.gnu.org Wed Nov 18 12:38:46 2020 Received: (at submit) by debbugs.gnu.org; 18 Nov 2020 17:38:47 +0000 Received: from localhost ([127.0.0.1]:36376 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kfRPq-0004Im-O2 for submit@debbugs.gnu.org; Wed, 18 Nov 2020 12:38:46 -0500 Received: from lists.gnu.org ([209.51.188.17]:40116) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kfRPn-0004Ic-Bz for submit@debbugs.gnu.org; Wed, 18 Nov 2020 12:38:45 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:44160) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kfRPn-0003bL-4r for bug-gnu-emacs@gnu.org; Wed, 18 Nov 2020 12:38:43 -0500 Received: from colin.muc.de ([193.149.48.1]:65334 helo=mail.muc.de) by eggs.gnu.org with smtp (Exim 4.90_1) (envelope-from ) id 1kfRPj-0004fG-QM for bug-gnu-emacs@gnu.org; Wed, 18 Nov 2020 12:38:42 -0500 Received: (qmail 23607 invoked by uid 3782); 18 Nov 2020 17:38:34 -0000 Received: from acm.muc.de (p4fe15a12.dip0.t-ipconnect.de [79.225.90.18]) by localhost.muc.de (tmda-ofmipd) with ESMTP; Wed, 18 Nov 2020 18:38:34 +0100 Received: (qmail 10314 invoked by uid 1000); 18 Nov 2020 17:38:34 -0000 Date: Wed, 18 Nov 2020 17:38:34 +0000 To: bug-gnu-emacs@gnu.org Subject: Uninitialised variables in syntax.c cause trouble. Message-ID: <20201118171726.GA10071@ACM> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Delivery-Agent: TMDA/1.1.12 (Macallan) From: Alan Mackenzie 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-detected-operating-system: by eggs.gnu.org: First seen = 2020/11/18 12:38:34 X-ACL-Warn: Detected OS = FreeBSD 9.x or newer [fuzzy] 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 autolearn=ham autolearn_force=no X-Spam_action: no action X-Spam-Score: -1.6 (-) X-Debbugs-Envelope-To: submit X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -2.6 (--) Hello, Emacs. On the master branch. In src/syntax.c, there are several uninitialised static variables, one of which is find_start_value. It is used in function find_defun_start before being initialised. The first use is at L.14 of the function, this: && pos >= find_start_value . This has the effect of causing a certain (forward-comment -1) (which calls back_comment, which calls find_defun_start) to fail. In my test setup (I am writing tests for syntax.c), find_start_value's value at loading time was randomly 1270, which was spuriously inside the comment I was trying to scan backwards over. back_comment thus failed to recognise the comment, and returned failed. All these variables need initialising to something if the code in syntax.c is to work properly. -- Alan Mackenzie (Nuremberg, Germany). From debbugs-submit-bounces@debbugs.gnu.org Wed Nov 18 12:57:50 2020 Received: (at 44724) by debbugs.gnu.org; 18 Nov 2020 17:57:50 +0000 Received: from localhost ([127.0.0.1]:36425 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kfRiI-0004nV-97 for submit@debbugs.gnu.org; Wed, 18 Nov 2020 12:57:50 -0500 Received: from mout.gmx.net ([212.227.17.20]:51915) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kfRiE-0004n8-3x for 44724@debbugs.gnu.org; Wed, 18 Nov 2020 12:57:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1605722258; bh=01MqJrfQY/j5A9nz8vR/ae4/bC1uJp8KJhlPlFcWUJY=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=S+RnW7DaIkMHSDqV2CXsw1B5+gaqK2+kkFtO/V63HD/EtikGkHAu+8CVX4t52N9K2 SjC7PLccA8KauuRNT07TGaSTjOZT1WOR6xLmN+CeQz9kBlrKV/OcOqfZTiQGXqfrhh 6A9EOHRN5CHRigaIfsNfFdwQXQZuF2o0BVywJIZM= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [192.168.1.102] ([46.125.249.84]) by mail.gmx.com (mrgmx105 [212.227.17.168]) with ESMTPSA (Nemesis) id 1MkYbu-1jzDTw2krm-00m2h8; Wed, 18 Nov 2020 18:57:38 +0100 Subject: Re: bug#44724: Uninitialised variables in syntax.c cause trouble. To: Alan Mackenzie , 44724@debbugs.gnu.org References: <20201118171726.GA10071@ACM> From: martin rudalics Message-ID: <1b64b1bf-b12e-7a13-2a33-4a308cf38873@gmx.at> Date: Wed, 18 Nov 2020 18:57:37 +0100 MIME-Version: 1.0 In-Reply-To: <20201118171726.GA10071@ACM> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K1:B5cCxpORs5Bk38cPeMoA15I1v1/j1bfZuJgf4mCBZCs864F8Y5i +59ThhQ2xZC8RdAcRKOmRIMNOukxnXOtiTBEsusg42ek/pYi/lsnSonDyGdNkViPKGs2xwo +CyesRvq0OFnXyRIK88VVszFUddiShQogbIJGtsMnYJOX8Xj/IUoerMn+DxtTzakesKQwGz OxyMTvU1bcR4mFtyDYhQw== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:ZyuBPZTnqZI=:hU0ZxtWyrhrnpUMCt8BkeV nkhqW+VwUIOwLUgm53zBL8jB5TBaJIFgIWggwQBv3kvviAEPRTwAqN+5ecK2vGvwIt3sqVu73 eyfE3NX1CqQV8ZeSm0nZijO/TYEfxK7+N7xVuD3RsIiV9P1BriEzJ2r8PrYQWwaVihJJZucmn fjn27KP8rQnNwvnqv0eVVjNFiVWo9m1Vp2LqwU5ptUkn1MdWAXOY5vYl2/6XkEc1iyCSv5jHs j6q9vl/TX1Q98L9j7TWgBw0YH56cRmEsMxRhAjKXsnp24Z9PRML6rgxv2QwIbmi1Vl/4BnxU6 wwRLKfnyX2fMbPLZ/Oeyp0Qh1eBme11h7yzjIfSb9tQswTJGcMd27wXXE/hZOQ4G7VKM2h0kj Ogv1y/fPk+ogWhkb91fxqctkTOQIpiyWMrTt8WwWLwkUBwKo3n2fRvWTZpOf5svRKaX0+aiRq 5g1w9JK2hi+hM2yaTsisdE8vka90kTTvQEOjalMG35J5VSdSocrl7LD5tn2N0xw35bA1K5m8v oT1rPRHzc0M4drMRguShRKxrerLnktRUsUIOXNd3gmyGdce4VzYR/7L46jFboA1qqtBcgfnTZ ty5QxbqQjeBeX9JORqsvXDKe0B2w1UG/PddOqbLKypTkrPcKL9p0yCwrwVdKQN8TOAT6FOzVo sh/KBpLiNeNePyY1+l8dD/xYvwGZaAYWu6SSNnxtNQPTrjU5Q/UG1DJA9SLocWqp53jjKHXho 6UoyUIQik+qN4w/ZRrwhLw6vqQziG73DI1yR2yjD+8hJi5KV5f/QBUx7cITT7wGeaZ4eiJhLT dzq93mjvHx7q+dYO3pUd0iV1DQc7qDf1c8HQtYlJXfCO7944X3IALe2+6pNvKRqAbOV8rEyh9 EtZS6RypcgoS+ZwkbysW9MNYLm5M6NIHL8NjdI4Pw= X-Spam-Score: 4.4 (++++) X-Spam-Report: Spam detection software, running on the system "debbugs.gnu.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: > In src/syntax.c, there are several uninitialised static variables, one of > which is find_start_value. > > It is used in function find_defun_start before being initialised. The > first use is at L. [...] Content analysis details: (4.4 points, 10.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 3.6 RCVD_IN_SBL_CSS RBL: Received via a relay in Spamhaus SBL-CSS [46.125.249.84 listed in zen.spamhaus.org] -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at https://www.dnswl.org/, low trust [212.227.17.20 listed in list.dnswl.org] -0.0 RCVD_IN_MSPIKE_H2 RBL: Average reputation (+2) [212.227.17.20 listed in wl.mailspike.net] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (rudalics[at]gmx.at) 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record 1.5 RCVD_IN_SORBS_WEB RBL: SORBS: sender is an abusable web server [46.125.249.84 listed in dnsbl.sorbs.net] X-Debbugs-Envelope-To: 44724 X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: 3.4 (+++) X-Spam-Report: Spam detection software, running on the system "debbugs.gnu.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: > In src/syntax.c, there are several uninitialised static variables, one of > which is find_start_value. > > It is used in function find_defun_start before being initialised. The > first use is at L. [...] Content analysis details: (3.4 points, 10.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_MSPIKE_H2 RBL: Average reputation (+2) [212.227.17.20 listed in wl.mailspike.net] 3.6 RCVD_IN_SBL_CSS RBL: Received via a relay in Spamhaus SBL-CSS [46.125.249.84 listed in zen.spamhaus.org] -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at https://www.dnswl.org/, low trust [212.227.17.20 listed in list.dnswl.org] 1.5 RCVD_IN_SORBS_WEB RBL: SORBS: sender is an abusable web server [46.125.249.84 listed in dnsbl.sorbs.net] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (rudalics[at]gmx.at) 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record -1.0 MAILING_LIST_MULTI Multiple indicators imply a widely-seen list manager > In src/syntax.c, there are several uninitialised static variables, one of > which is find_start_value. > > It is used in function find_defun_start before being initialised. The > first use is at L.14 of the function, this: > > && pos >= find_start_value > > . This has the effect of causing a certain (forward-comment -1) (which > calls back_comment, which calls find_defun_start) to fail. > > In my test setup (I am writing tests for syntax.c), find_start_value's > value at loading time was randomly 1270, which was spuriously inside the > comment I was trying to scan backwards over. back_comment thus failed to > recognise the comment, and returned failed. Just curious: Did current_buffer == find_start_buffer really succeed in your scenario? martin From debbugs-submit-bounces@debbugs.gnu.org Wed Nov 18 15:26:21 2020 Received: (at 44724) by debbugs.gnu.org; 18 Nov 2020 20:26:21 +0000 Received: from localhost ([127.0.0.1]:36586 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kfU21-00026F-4v for submit@debbugs.gnu.org; Wed, 18 Nov 2020 15:26:21 -0500 Received: from colin.muc.de ([193.149.48.1]:17331 helo=mail.muc.de) by debbugs.gnu.org with smtp (Exim 4.84_2) (envelope-from ) id 1kfU1y-000260-3k for 44724@debbugs.gnu.org; Wed, 18 Nov 2020 15:26:20 -0500 Received: (qmail 39456 invoked by uid 3782); 18 Nov 2020 20:26:11 -0000 Received: from acm.muc.de (p4fe15a12.dip0.t-ipconnect.de [79.225.90.18]) by localhost.muc.de (tmda-ofmipd) with ESMTP; Wed, 18 Nov 2020 21:26:10 +0100 Received: (qmail 12530 invoked by uid 1000); 18 Nov 2020 20:26:10 -0000 Date: Wed, 18 Nov 2020 20:26:10 +0000 To: martin rudalics Subject: Re: bug#44724: Uninitialised variables in syntax.c cause trouble. Message-ID: <20201118202610.GB10071@ACM> References: <20201118171726.GA10071@ACM> <1b64b1bf-b12e-7a13-2a33-4a308cf38873@gmx.at> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1b64b1bf-b12e-7a13-2a33-4a308cf38873@gmx.at> X-Delivery-Agent: TMDA/1.1.12 (Macallan) From: Alan Mackenzie X-Primary-Address: acm@muc.de X-Spam-Score: 0.0 (/) X-Debbugs-Envelope-To: 44724 Cc: 44724@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -1.0 (-) Hello, Martin. On Wed, Nov 18, 2020 at 18:57:37 +0100, martin rudalics wrote: > > In src/syntax.c, there are several uninitialised static variables, one of > > which is find_start_value. > > It is used in function find_defun_start before being initialised. The > > first use is at L.14 of the function, this: > > && pos >= find_start_value > > . This has the effect of causing a certain (forward-comment -1) (which > > calls back_comment, which calls find_defun_start) to fail. > > In my test setup (I am writing tests for syntax.c), find_start_value's > > value at loading time was randomly 1270, which was spuriously inside the > > comment I was trying to scan backwards over. back_comment thus failed to > > recognise the comment, and returned failed. > Just curious: Did current_buffer == find_start_buffer really succeed > in your scenario? Yes it did. All four comparisons in that block of code succeeded, causing a spurious value to be returned by find_defun_start. But now I think that that value was a previously valid one which just hadn't been updated on buffer changes. I don't think there's any cache invalidation code associated with this cache, and I think that's why it gave an invalid result. > martin -- Alan Mackenzie (Nuremberg, Germany). From debbugs-submit-bounces@debbugs.gnu.org Thu Nov 19 03:26:02 2020 Received: (at 44724) by debbugs.gnu.org; 19 Nov 2020 08:26:02 +0000 Received: from localhost ([127.0.0.1]:38060 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kffGU-0003oz-Iy for submit@debbugs.gnu.org; Thu, 19 Nov 2020 03:26:02 -0500 Received: from mout.gmx.net ([212.227.15.19]:37915) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kffGQ-0003oT-ON for 44724@debbugs.gnu.org; Thu, 19 Nov 2020 03:26:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1605774351; bh=XNvgix13Fyendm9y6vJUohJF5D6rnm2jFZh16rWvdJo=; h=X-UI-Sender-Class:Subject:To:Cc:References:From:Date:In-Reply-To; b=EVBCJvjT7zpEkX+xWY8yLz/Hg1DM4Q7ACuteXvFBfX02ah44dwAeQyc2rdRCtNoz5 4ZRDVx1FJhM6INSOTQCEbdRf8bhzdst6Mcy3g3/JdcjwWtkEyMs5+6lHjqogc0G4ig jGUxE5XnPIas0K7PiCSx06eCAIYQR+ky/j8XGg88= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [192.168.1.100] ([212.95.5.202]) by mail.gmx.com (mrgmx004 [212.227.17.190]) with ESMTPSA (Nemesis) id 1MqaxO-1jtO9v2bXk-00mYbX; Thu, 19 Nov 2020 09:25:51 +0100 Subject: Re: bug#44724: Uninitialised variables in syntax.c cause trouble. To: Alan Mackenzie References: <20201118171726.GA10071@ACM> <1b64b1bf-b12e-7a13-2a33-4a308cf38873@gmx.at> <20201118202610.GB10071@ACM> From: martin rudalics Message-ID: Date: Thu, 19 Nov 2020 09:25:50 +0100 MIME-Version: 1.0 In-Reply-To: <20201118202610.GB10071@ACM> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K1:0hyKhOMRf8g57GJsDjFxB0j9McQAJh5PIt7VRzq35EUHjboORRi P4mLtmGwEY+IMzYJ2iqMirDKpK8DbJ+5Al3CmnGYVlnaX2JqKJHGYE1/ySAk1sOSKnqzBuh NggTlD/BfiI8O9lV+T8IDJY0otqXyZcAjkQ5b+FINL+PzehjC4CM/Oo9ZzaTyMiCe0bp7S0 Tf68yBp25BIndZyeGvgwA== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:+NPY7yK+KGE=:ahKmPnoZChQMjERt1UjVrY rihVI7UlZ8tDU5Be1+UAPigwPSYmXZW+bDVM1spOejHXYxIVJjrY2pTBNH5zmTkUxinaXSMRR aRnaEJslP11HbbLa1Kmf8sO65j+oRmVKEYESCEa25iFa4Tv//44QEDkt32hCER1xfnegSjn70 IXM+O3GOCcVquiv6WOd9Pfx8FH7Utz2PgG1jdt9BD0r8LinTGx5+fMHVVw1xMAFK+LdZl9qTK qD9Wm5FKXinS7Nb7PXLHchG6g+5LdchZy2FLyAmfWog3QzTsdRwSmKy2fuOQsNAWJWD0rFV/z bKGsUdcjN8kEUGNgVKCRTeWTuJ5apGdZXm9oIL8HVBUE1/y+gqgSpKE1OIIIQdsfjgcPCCukq U1jOcUln2XIfMaLmaoUsi6DXs6S9VxkeAEskahk2pAg+Pw4Qp3GtW5tclMd6/z1o4RSz/Fj3z Rk/FJtMbQPq2FOYeRAnqs2dprofDOVGFVuuVjKPowQgoExTGoiKc8pPjIg8AZMf8SxK9ff4w4 +0UUmhhcZAV14JAhuqiM3WXe2qItN5EUML5/a7uVZUTzWyeJEoIDeMUxvwAETrZboo/s4cSo8 CGXntCGxepy7v8hsa4NmZrZHEVTixpJI3YsaKrcSrMnIHeVicieRrvdbC9CK/ahNaaTh4Py4u ZTAHytd38Osr2Todiab5vcfNh+BJnbosutxkGj2TSet4RBmC42eJRMOxUayJIhWonbt4HXrs2 RDEDcE0FHA1QodkI/MK3lg2sJpFlWIooGVCvtogQjrmptMzWLjIc3CLKNVoQr1FTj1n5gNgqC 1OyXkKxKF1IBZo6rCyicdkqsGb2Xxbdcrgq0puzhlYocmsauGMau6o88wylkfntr/HAzEIBjH Tcl7rvyurmp1lLcuD+Mw== X-Spam-Score: -0.7 (/) X-Debbugs-Envelope-To: 44724 Cc: 44724@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -1.7 (-) >> Just curious: Did current_buffer == find_start_buffer really succeed >> in your scenario? > > Yes it did. All four comparisons in that block of code succeeded, > causing a spurious value to be returned by find_defun_start. Isn't the probability for such a thing to be caused by uninitialized variables lower than that of the Emacs tagging scheme to fail as a whole? > But now I think that that value was a previously valid one which just > hadn't been updated on buffer changes. > > I don't think there's any cache invalidation code associated with this > cache, MODIFF == find_start_modiff > and I think that's why it gave an invalid result. martin From debbugs-submit-bounces@debbugs.gnu.org Thu Nov 19 11:30:41 2020 Received: (at 44724) by debbugs.gnu.org; 19 Nov 2020 16:30:41 +0000 Received: from localhost ([127.0.0.1]:40771 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kfmpU-0001pn-S5 for submit@debbugs.gnu.org; Thu, 19 Nov 2020 11:30:41 -0500 Received: from colin.muc.de ([193.149.48.1]:12888 helo=mail.muc.de) by debbugs.gnu.org with smtp (Exim 4.84_2) (envelope-from ) id 1kfmpT-0001pZ-6F for 44724@debbugs.gnu.org; Thu, 19 Nov 2020 11:30:39 -0500 Received: (qmail 42650 invoked by uid 3782); 19 Nov 2020 16:30:32 -0000 Received: from acm.muc.de (p4fe153fb.dip0.t-ipconnect.de [79.225.83.251]) by localhost.muc.de (tmda-ofmipd) with ESMTP; Thu, 19 Nov 2020 17:30:31 +0100 Received: (qmail 19446 invoked by uid 1000); 19 Nov 2020 16:30:32 -0000 Date: Thu, 19 Nov 2020 16:30:32 +0000 To: martin rudalics Subject: Re: bug#44724: Uninitialised variables in syntax.c cause trouble. Message-ID: <20201119163032.GD6259@ACM> References: <20201118171726.GA10071@ACM> <1b64b1bf-b12e-7a13-2a33-4a308cf38873@gmx.at> <20201118202610.GB10071@ACM> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Delivery-Agent: TMDA/1.1.12 (Macallan) From: Alan Mackenzie X-Primary-Address: acm@muc.de X-Spam-Score: 0.0 (/) X-Debbugs-Envelope-To: 44724 Cc: 44724@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -1.0 (-) Hello, Martin. On Thu, Nov 19, 2020 at 09:25:50 +0100, martin rudalics wrote: > >> Just curious: Did current_buffer == find_start_buffer really succeed > >> in your scenario? > > Yes it did. All four comparisons in that block of code succeeded, > > causing a spurious value to be returned by find_defun_start. > Isn't the probability for such a thing to be caused by uninitialized > variables lower than that of the Emacs tagging scheme to fail as a > whole? Yes. > > But now I think that that value was a previously valid one which just > > hadn't been updated on buffer changes. > > I don't think there's any cache invalidation code associated with this > > cache, > MODIFF == find_start_modiff Yes, thanks, I was wrong there. > > and I think that's why it gave an invalid result. I've found out what my problem is. find_defun_start, unless one takes precautions against it, calls syntax-ppss, which in my situation was uninitialised. There is nothing in Emacs to cause the initialisation of syntax-ppss when, say, the syntax-table is changed. It all needs to be done by hand. I'll close this bug as not a bug. Thanks for all the help! > martin -- Alan Mackenzie (Nuremberg, Germany). From debbugs-submit-bounces@debbugs.gnu.org Tue Nov 24 03:02:48 2020 Received: (at 44724) by debbugs.gnu.org; 24 Nov 2020 08:02:48 +0000 Received: from localhost ([127.0.0.1]:57328 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1khTHk-0007nh-1R for submit@debbugs.gnu.org; Tue, 24 Nov 2020 03:02:48 -0500 Received: from quimby.gnus.org ([95.216.78.240]:50568) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1khTHi-0007nS-Uo for 44724@debbugs.gnu.org; Tue, 24 Nov 2020 03:02:47 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnus.org; s=20200322; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date: References:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=HlJrl27joInaoNPJWpRSfV8H04AeItdMy82h3wAHIqw=; b=jP4uUrIVS9SoVSt/ufsFjs4aiN 21FuLP5BoCZqHD51ypHLj3oEPFLq0+EafrxirksDWDZHQEvrHuelVyN74Ytealw+yLpTKSYbNzf3i chwuRytBwuADj+6vbyLZEXGscwaUDtEncAm7+MWsEczvkf+WP1SQa8E9EKkkuC/hgVX8=; Received: from cm-84.212.202.86.getinternet.no ([84.212.202.86] helo=xo) by quimby.gnus.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1khTHT-00013Z-Ak; Tue, 24 Nov 2020 09:02:41 +0100 From: Lars Ingebrigtsen To: Alan Mackenzie Subject: Re: bug#44724: Uninitialised variables in syntax.c cause trouble. References: <20201118171726.GA10071@ACM> <1b64b1bf-b12e-7a13-2a33-4a308cf38873@gmx.at> <20201118202610.GB10071@ACM> <20201119163032.GD6259@ACM> X-Now-Playing: Fad Gadget's _Fireside Favourites_: "Fireside Favourite" Date: Tue, 24 Nov 2020 09:02:29 +0100 In-Reply-To: <20201119163032.GD6259@ACM> (Alan Mackenzie's message of "Thu, 19 Nov 2020 16:30:32 +0000") Message-ID: <87y2ir6v3e.fsf@gnus.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Spam-Report: Spam detection software, running on the system "quimby.gnus.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see @@CONTACT_ADDRESS@@ for details. Content preview: Alan Mackenzie writes: > I'll close this bug as not a bug. This wasn't done, so I'm doing that now. Content analysis details: (-2.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-Spam-Score: 0.0 (/) X-Debbugs-Envelope-To: 44724 Cc: martin rudalics , 44724@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -1.0 (-) Alan Mackenzie writes: > I'll close this bug as not a bug. This wasn't done, so I'm doing that now. -- (domestic pets only, the antidote for overdose, milk.) bloggy blog: http://lars.ingebrigtsen.no From debbugs-submit-bounces@debbugs.gnu.org Tue Nov 24 03:02:54 2020 Received: (at control) by debbugs.gnu.org; 24 Nov 2020 08:02:54 +0000 Received: from localhost ([127.0.0.1]:57333 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1khTHq-0007o4-85 for submit@debbugs.gnu.org; Tue, 24 Nov 2020 03:02:54 -0500 Received: from quimby.gnus.org ([95.216.78.240]:50584) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1khTHp-0007ng-67 for control@debbugs.gnu.org; Tue, 24 Nov 2020 03:02:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnus.org; s=20200322; h=Subject:From:To:Message-Id:Date:Sender:Reply-To:Cc: MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=szhBxmSDL4iPcLcj4SWdjkSznRkVoZJpereyJTF00r0=; b=KvFQN8Oxkiq5faYVIUZeZAeb0J m4TDGAyx5MQbr1VWtPRcDDKium35UfUi000nC0HY/Fx7JyHx7XeAhVppq2rsEDVfDevzpgSBjkC2Q KwsON/oNrJGOK4V3dkxR0s6eX0sFZV1lwmNSjVS42lkOZKB/lRx07/6knAuUBDnB78qE=; Received: from cm-84.212.202.86.getinternet.no ([84.212.202.86] helo=xo) by quimby.gnus.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1khTHh-00013l-EL for control@debbugs.gnu.org; Tue, 24 Nov 2020 09:02:47 +0100 Date: Tue, 24 Nov 2020 09:02:44 +0100 Message-Id: <87wnyb6v2z.fsf@gnus.org> To: control@debbugs.gnu.org From: Lars Ingebrigtsen Subject: control message for bug #44724 X-Spam-Report: Spam detection software, running on the system "quimby.gnus.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see @@CONTACT_ADDRESS@@ for details. Content preview: tags 44724 notabug close 44724 quit Content analysis details: (-2.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-Spam-Score: 0.0 (/) X-Debbugs-Envelope-To: control X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: debbugs-submit-bounces@debbugs.gnu.org Sender: "Debbugs-submit" X-Spam-Score: -1.0 (-) tags 44724 notabug close 44724 quit From unknown Sat Jun 14 03:47:28 2025 Received: (at fakecontrol) by fakecontrolmessage; To: internal_control@debbugs.gnu.org From: Debbugs Internal Request Subject: Internal Control Message-Id: bug archived. 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