From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.130]) by sourceware.org (Postfix) with ESMTPS id 78FBD3939C04 for ; Mon, 8 Mar 2021 14:01:39 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 78FBD3939C04 Received: from calimero.vinschen.de ([24.134.7.25]) by mrelayeu.kundenserver.de (mreue010 [212.227.15.167]) with ESMTPSA (Nemesis) id 1MJmbB-1l4CZS1OjB-00KCZd for ; Mon, 08 Mar 2021 15:01:35 +0100 Received: by calimero.vinschen.de (Postfix, from userid 500) id 00EB8A80708; Mon, 8 Mar 2021 15:01:35 +0100 (CET) Date: Mon, 8 Mar 2021 15:01:34 +0100 From: Corinna Vinschen To: cygwin@cygwin.com Subject: Re: segfault on 32bit cygwin snapshot Message-ID: Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: <20210304180534.7c3825e6ee989a2bf62f0652@nifty.ne.jp> <20210304205000.4ac34afe1a8b767ea2986291@nifty.ne.jp> <98df59b3-a139-03d2-c8c5-31ff4f8448ab@gmail.com> <625cb9d2-b6cc-3ada-eea9-44a5e73da17c@gmail.com> <72a86908-e150-2070-24f7-79ca82de9916@maxrnd.com> <7b34da67-7550-765b-3731-31b51b2a5df9@maxrnd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <7b34da67-7550-765b-3731-31b51b2a5df9@maxrnd.com> X-Provags-ID: V03:K1:DCEpFJPn6TMGRBefaBJR/AVSiUwFTvQKgj0HGzJe4AGshz1X+Ym k2NlCIn6QkTtovenvpMGYvV6+a2Wz3hLPT2phqLr6pX4DdsfyWSqf0Ms4ytPcuZK/mgipqE LiywStKN8BytxgV3xhZsjWZOaYMTE70G+tlEJyBgruXxyoYMpINP9Lp25lFWrfnJtj6Zb5N X3ggPMWkiSlKX5gOalhSg== X-UI-Out-Filterresults: notjunk:1;V03:K0:F0tvq6l1YrA=:MVAIS2a336sQhY7Zv4wmuw PXFh2t64ieaPdvWxh5+7aQXUKXzWprRDVJDiOKb5jiaFYYFKpwZL6LuxGp8PQaCb1dy3uYNgZ gvrj0khjcYFiMdZftErN8/NkSMtgWDFgMatQm+VPOFVuLWtO+i38XoGHmBKmMVMCNlCJeolV9 UnONhmdMrHwjZ+tBOvCO+95GHozn7VC8MlbDiPMasJtUwFGmpvB9wr/hB4B4xnJcE2+IAxgq/ QeEriYJluo8RlxZ8YbiTnvTwOneaSP5h+kWAudxHjY8vfwY9Qve9rvp0vvK32hO3SnZYHhdcU 0u/U7qxOtON3nx/tUfKjgt0T9CpPh1Mpd+bu2Brq7oJZ12y7INRSVEY7hbrujaRZxHDeDXMWg sq0+iEdYA3cwAhaoaLaWJNJX/9qBx7GZULt2WwdaM6WXZ33ytToXpIkIHSUfuwLvDrlGAb8MJ XPZewpZEJg== X-Spam-Status: No, score=-99.8 required=5.0 tests=BAYES_00, BODY_8BITS, GOOD_FROM_CORINNA_CYGWIN, KAM_DMARC_NONE, KAM_DMARC_STATUS, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NEUTRAL, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: cygwin@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: General Cygwin discussions and problem reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 08 Mar 2021 14:01:41 -0000 On Mar 8 03:07, Mark Geisert wrote: > Following up to myself... > > Mark Geisert wrote: > > Hi Corinna, > > > > On Fri, 5 Mar 2021, Corinna Vinschen wrote: > > > On Mar  5 01:11, Mark Geisert wrote: > > > > Marco Atzeri via Cygwin wrote: > > > > > On 04.03.2021 21:17, Marco Atzeri wrote: > > > > > > On 04.03.2021 16:17, Ken Brown via Cygwin wrote: > > > > > > > On 3/4/2021 6:50 AM, Takashi Yano via Cygwin wrote: > > > > > > > > On Thu, 4 Mar 2021 12:11:11 +0100 > > > > > > > > marco atzeri wrote: > > > > > > > > > I have no problem to patch Python to solve the issue, > > > > > > > > > but I have not seen evidence of the dlsym mechanism . > > > > > > > > > But of course I an NOT and expert in this field. > > > > > > > > > > > > > > > > > > If someone looking to the code can give me some hints, > > > > > > > > > I will appreciate > > > > > > > > > > > > > > > > I am also not sure where the dlsym() is used in python. > > > > > > > > At least, os.uname() works in python 3.8.7 and 2.7.18 in my > > > > > > > > environment even without that snippet. It seems that os.uname() > > > > > > > > does not use dlsym(). Do I overlook something? > > > > > > > > > > > > > > This all started because Mark reported a problem building python 3.8.3: > > > > > > > > > > > > > >    https://cygwin.com/pipermail/cygwin-apps/2020-December/040765.html > > > > > > > https://cygwin.com/pipermail/cygwin-developers/2020-December/012019.html > > > > > > > > > > > > > > It's strange that Marco never bumped into the problem. > > > > > > > > > > > > > > Ken > > > > > > > > > > > > I never built python using cygwin snapshots as Mark was trying to do, > > > > > > all my builds were using 3.1.7. > > > > > > > > > > > > Let me set a separate enviroment for building on latest snapshot > > > > > > > > > > I can not replicate with latest snapshot > > > > > > > > > > $ uname -svr > > > > > CYGWIN_NT-10.0-WOW 3.2.0s(0.340/5/3) 2021-03-01 15:42 > > > > > > > > > > nor in 64bit when building 3.8.8 > > > > > > > > > > For what I see the DLL is always using a proper import > > > > > from cygwin1.dll > > > > > > > > > > $ objdump -x libpython3.8.dll |grep uname > > > > >          2b9de0   2170  uname > > > > >          2b9de8   2171  uname_x > > > > > > > > > > the only thing not standard on my build system is a case sensitive > > > > > filesystem and mount > > > > > > > > I had concerns that I had somehow corrupted my build environment, and it was > > > > Marco's successes that convinced me to reinstall 3.1.7 to recover a > > > > known-good environment.  Then seeing Marco go ahead and release the > > > > different Python releases (yay!) I didn't investigate any further. > > > > > > > > I'm now trying to locate the os.uname usage of dlopen/dlsym again just for > > > > the record but am having some difficulty.  I'll reply again when I've got > > > > it. > > > > > > Guys, > > > > > > if it turns out that we fixed a problem that doesn't actually is a > > > real-world problem, I'm wondering if we shouldn't just revert the Cygwin > > > patch we're talking about here (commit 532b91d24e9496) and be done with > > > it. > > > > > > Special casing dynamic loading of uname just to support some experimental > > > bordercase doesn't make much sense.  In that case I'm all for "don't do > > > that"! > > > > That may well be the appropriate endpoint, but please let me dig a > > little further into the recent Python versions.  The fact that they had > > an explicit dlopen/dlsym to get at uname(), but now they don't, troubles > > me. I want to be sure us Cygwin folk aren't in an inadvertent "arms > > race" with the Python devs over the uname API change.  Dunno why this > > didn't occur 15+ years ago, but here we are. > > > > I think it was in Python's Modules/posixmodule.c.  They're certainly > > using uname() directly in their most recent builds.  But I believe that > > wasn't always the case, even just a few months ago.  Let me dig for a > > day or two. > > Not to put too fine a point on it, but I now believe I hit the issue I > reported due to my own corrupted build environment. Marco and Ken have both > built recent Python packages on Cygwin 3.1.7 and proto-3.2.0 respectively, > Ken having reverted the commit you're talking about (not sure about Marco). > Both had success. > > I believe reverting that commit 532b91d24e9496 is the correct action to take. Did so this morning. Thanks, Corinna