From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id B71E542C52 for ; Mon, 2 May 2022 19:24:38 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id C8D7868B2BE; Mon, 2 May 2022 22:24:35 +0300 (EEST) Received: from mail8.parnet.fi (mail8.parnet.fi [77.234.108.134]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id D27D468A34B for ; Mon, 2 May 2022 22:24:28 +0300 (EEST) Received: from mail9.parnet.fi (mail9.parnet.fi [77.234.108.21]) by mail8.parnet.fi with ESMTP id 242JOR7r019091-242JOR7s019091 for ; Mon, 2 May 2022 22:24:27 +0300 Received: from foo.martin.st (host-97-187.parnet.fi [77.234.97.187]) by mail9.parnet.fi (Postfix) with ESMTPS id 5B02AA142C for ; Mon, 2 May 2022 22:24:27 +0300 (EEST) Date: Mon, 2 May 2022 22:24:25 +0300 (EEST) From: =?ISO-8859-15?Q?Martin_Storsj=F6?= To: FFmpeg development discussions and patches In-Reply-To: <9gALEgkn.1651513526.6738600.dif@localhost> Message-ID: <4e95b537-99f5-7813-a0cd-387e8f66150@martin.st> References: <9gALEgkn.1651513526.6738600.dif@localhost> MIME-Version: 1.0 X-FE-Policy-ID: 3:14:2:SYSTEM Subject: Re: [FFmpeg-devel] PATCH - libmad MP3 decoding support X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: On Mon, 2 May 2022, David Fletcher wrote: > On 2/5/2022, "Nicolas George" wrote: >> Is there a trac ticket? If not, please fill one: we would not want to >> keep that bug. >> >> Regards, >> >> -- >> Nicolas George > > Hi Nicolas, > > I'll prepare a test case to demonstrate the issue and fill in a ticket. > As far as I can tell this is an issue affecting older ARM hardware, it > cannot be reproduced on x86 hardware. I now have some additional ARM > hardware with a more capable CPU which should help pin down the problem. That sounds like there's an issue with some of the ARM implementations of DSP functions, that only exists in implementations for less featureful ARM instruction sets. (It could theoretically be a compiler bug also but I think it's much more probable that it's a bug in a seldom used codepath in ffmpeg.) If you pass "-cpuflags 0" to ffmpeg, does the issue vanish? (If it does, it would suggest an issue in e.g. an armv5/armv6 specific implementation of some DSP functions.) Does if vanish if you configure with --arch=generic? (That would omit all ARM specific DSP routines and just use plain C code.) On a more modern ARM cpu, if it works correctly normally, does the issue appear if you use "-cpuflags 0"? That would indicate an issue in one of the ARM specific routines that are enabled without cpuflags (e.g. that don't require anything above armv4). // Martin _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".