X-Recipient: archive-cygwin AT delorie DOT com DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:references :in-reply-to:content-type:content-id:content-transfer-encoding :mime-version; q=dns; s=default; b=ZrZYIyWDdanoFSorBSBOL8rPBPyvM 06c/KhmGD37BZjtLCo8Q18KqoqbjaKw2ZMDWxI1g5fdDQiWvUODxVrNTExI+3wyC OfrSgf6jNcJPqF1pTBWdFJ3xJdYOiL2g5abFwVhwTC4biZ3fB6mfeGl0Jm4bQQu6 gqwAB5/Yh0VjjE= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:references :in-reply-to:content-type:content-id:content-transfer-encoding :mime-version; s=default; bh=gLPI3vdDSPEszGitWZQnscXbEkI=; b=wLv wjnTQVKsexX4qlNXJnb2zRC//Gkw3ppAVIZ0pXUn7uVZAwUKFCTAtVouDtJgg6jH L5oK/ozRh0I+wZlOQyV+ZFPvKKlCxfAJR0mofDJq3YF0tzyu+0FAu1wb9HRTUYku OU52bR7+Ib3C/NJBQq1x1APXThLGpgFa2oGRD3x8= Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_NONE,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.1 spammy=k X-HELO: NAM04-CO1-obe.outbound.protection.outlook.com ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=lKHH3oyP1B8zlu2RhyY3a9CfqeS2MdPPAfcyeUT9cJTp0AzBM4P+2AgmMVnU95s7Nrz1vN7mBu/FdSHadrXWRy665NITdKnrxho4VZrRqv6unnas0MF/OsJBcvggHF6TFiOj85q1AOp9p7YAj9jTfgBjlKXHATt3ZBvj/6glC2Hbcck6s3VLIo4hDDEsz6eRLkK3wscQPhBXo4TA7N/VSsTse2Hxt0rNpnbwtk1ZtEXtg6INjGvhDM1HQTKHwIngle2p6GWQ+msPQ0oBwxoClmSdA3MhAJGzIcsnlu4whFRXoyjiGnUdU5FdbgHLlGK5sXqhVZbvuMcBBNQRQcjvaQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=97vbvUiFpTkiHa6o5fWtGBwDRzoce2kXU94yyAZXWmU=; b=h3Az6CV2z68PKfaGimsMM32FwrPO821wp0gemWPNpbBbjKY/uQcht45Nf2WWEs58Wjt28Hc/5G90zI3voiY8v7QKBRbPJNMUOg0TfhW5GHCY4R+YoFQm46Vf3ggK6cQsUQ+oEmaopnlJ/VRnLgpqvcpF+5L1t/nRts0HOScmXIsDj8RvrRQnAz0YvPQdG0Y1ixKwrdVmk/CzWwnvYupbawdm5T7ltlNO++W/YDUw0xHnNNfq1tz7sgM8apfG7B8CnMqTyDOQb9MAApzY+ZgCuQ/61Sh7rDvLmFH2YczrFL2Zy1Ask1AMOoMpd84opBlEyHKl43ABG5U+ktLCI+oM7Q== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=cornell.edu; dmarc=pass action=none header.from=cornell.edu; dkim=pass header.d=cornell.edu; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cornell.edu; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=97vbvUiFpTkiHa6o5fWtGBwDRzoce2kXU94yyAZXWmU=; b=eOh1JJ+fxZVYy/rNDfJq3DJztwwytRqEqErb+lUv8G0XjQfBwuqRZqs3ffVMzfRRUUSRKKOlWy4Iu6AhmUiL1BJTVPFlHk2+r05hdUpz/cgcoWbU/APvnpGd+cwLr44N0Tlp89BEJua0267fiV+LsdgjXlMtll2mk1pH7YwWEKA= From: Ken Brown To: "cygwin AT cygwin DOT com" CC: =?utf-8?B?UGV0ciBTa2/EjcOtaw==?= Subject: Re: malloc(0) crashing with SIGABRT Date: Thu, 12 Sep 2019 16:12:36 +0000 Message-ID: References: <366918d8-b505-45be-dc28-303579f17341 AT gmail DOT com> <78e19eb7-956e-cd05-a076-e56ce347bbbe AT gmail DOT com> In-Reply-To: <78e19eb7-956e-cd05-a076-e56ce347bbbe@gmail.com> user-agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 authentication-results: spf=none (sender IP is ) smtp.mailfrom=kbrown AT cornell DOT edu; x-ms-exchange-purlcount: 1 x-ms-oob-tlc-oobclassifiers: OLM:6430; received-spf: None (protection.outlook.com: cornell.edu does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-ms-exchange-transport-forked: True Content-Type: text/plain; charset="utf-8" Content-ID: <130D5FF3F86C4B47888B7DC167F31558 AT namprd04 DOT prod DOT outlook DOT com> MIME-Version: 1.0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: IAyeA2bttB0j5+c1MVQpkUXwZ3cMusN4wm5PCfLCcLmxNbJHgPlIzWEQqobFnoYEtFevYNANPL2JkgjAX+W4HQ== X-IsSubscribed: yes Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by delorie.com id x8CGDEAi030644 On 9/9/2019 1:13 PM, Petr Skočík wrote: > There's been a twitter discussion on how different POSIX platforms > handle malloc(0): https://twitter.com/sortiecat/status/1170697927804817412 . > > As for Cygwin, the answer appears to be "not well", but this should be > easy to fix. Can you show how you produced a crash? It works fine for me with the following test program: $ cat malloc_zero.c #include #include int main () { printf ("malloc (0) = %p\n", malloc (0)); } $ gcc -Wall -o malloc_zero malloc_zero.c $ ./malloc_zero.exe malloc (0) = 0x8000003c0 [This is on 64-bit Cygwin. It's the same on 32-bit, but with a different address.] Ken -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple