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([2607:fb90:f20b:1885:28a8:1eff:fe1b:3320]) by smtp.gmail.com with ESMTPSA id m6-20020a9d73c6000000b006860be3a43fsm7631822otk.14.2023.01.19.19.19.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 19 Jan 2023 19:19:01 -0800 (PST) Message-ID: <0f51dac4-836b-0ff2-38c6-5521745c1c88@landley.net> Date: Thu, 19 Jan 2023 21:31:21 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.5.0 Subject: Re: Calculating array sizes in C - was: Re: Build regressions/improvements in v6.2-rc1 Content-Language: en-US To: "Michael.Karcher" , John Paul Adrian Glaubitz , Geert Uytterhoeven Cc: linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-wireless@vger.kernel.org, linux-mips@vger.kernel.org, linux-sh@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linuxppc-dev@lists.ozlabs.org, kasan-dev@googlegroups.com, linux-xtensa@linux-xtensa.org, Michael Karcher , Arnd Bergmann References: <20221227082932.798359-1-geert@linux-m68k.org> <3800eaa8-a4da-b2f0-da31-6627176cb92e@physik.fu-berlin.de> <429140e0-72fe-c91c-53bc-124d33ab5ffa@physik.fu-berlin.de> <0d238f02-4d78-6f14-1b1b-f53f0317a910@physik.fu-berlin.de> <1732342f-49fe-c20e-b877-bc0a340e1a50@fu-berlin.de> From: Rob Landley In-Reply-To: <1732342f-49fe-c20e-b877-bc0a340e1a50@fu-berlin.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org On 1/19/23 16:11, Michael.Karcher wrote: > Isn't this supposed to be caught by this check: >>>> >>>>          a, __same_type(a, NULL) >>>> >>>> ? >>> >>> Yeah, but gcc thinks it is smarter than us... >>> Probably it drops the test, assuming UB cannot happen. >> Hmm, sounds like a GGC bug to me then. Not sure how to fix this then. > > > I don't see a clear bug at this point. We are talking about the C expression > >   __same_type((void*)0, (void*)0)? 0 : sizeof((void*)0)/sizeof(*((void*0)) *(void*) is type "void" which does not have a size. The problem is gcc "optimizing out" an earlier type check, the same way it "optimizes out" checks for signed integer math overflowing, or "optimizes out" a comparison to pointers from two different local variables from different function calls trying to calculate the amount of stack used, or "optimizes out" using char *x = (char *)1; as a flag value and then doing "if (!(x-1)) because it can "never happen"... > I suggest to file a bug against gcc complaining about a "spurious > warning", and using "-Werror -Wno-error-sizeof-pointer-div" until gcc is > adapted to not emit the warning about the pointer division if the result > is not used. Remember when gcc got rewritten in c++ starting in 2007? Historically the main marketing push of C++ was that it contains the whole of C and therefore MUST be just as good a language, the same way a mud pie contains an entire glass of water and therefore MUST be just as good a beverage. Anything C can do that C++ _can't_ do is seen as an existential threat by C++ developers. They've worked dilligently to "fix" C not being a giant pile of "undefined behavior" the way C++ is for 15 years now. I have... opinions on this. > Regards, >   Michael Karcher Rob From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 51D1FC004D4 for ; Fri, 20 Jan 2023 03:20:08 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Nyl9f3wfWz3fJD for ; Fri, 20 Jan 2023 14:20:06 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=landley-net.20210112.gappssmtp.com header.i=@landley-net.20210112.gappssmtp.com header.a=rsa-sha256 header.s=20210112 header.b=195AXt9o; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=landley.net (client-ip=2607:f8b0:4864:20::330; helo=mail-ot1-x330.google.com; envelope-from=rob@landley.net; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=landley-net.20210112.gappssmtp.com header.i=@landley-net.20210112.gappssmtp.com header.a=rsa-sha256 header.s=20210112 header.b=195AXt9o; dkim-atps=neutral Received: from mail-ot1-x330.google.com (mail-ot1-x330.google.com [IPv6:2607:f8b0:4864:20::330]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Nyl8X5lGZz3c6F for ; Fri, 20 Jan 2023 14:19:06 +1100 (AEDT) Received: by mail-ot1-x330.google.com with SMTP id k44-20020a9d19af000000b00683e176ab01so2370713otk.13 for ; Thu, 19 Jan 2023 19:19:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=landley-net.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=WxJtcfmjg8bDlWo77QXfqDNdo8CBClhx9W/RQtlqbwY=; b=195AXt9odDu2myrtF32+GBb0qMFgjNikCrpxsa+WbA8hIOrugiKzMmRa6ck9jEEnh+ BAiMUjeACSwa7DIsy0nd31WMLgqeemkaP54UGh/z5/4/iE4OKfk/JF3Mfjc9Slk04hNo yl5Eob9OFP8rjo94KXNck41rTFVGwR12Dn+yA5SLoZAqZ3VzofVm+vx+0BgQAYSmr785 93R2tgLtdgq0ZrmMjpy2ltpjwYB3CfaG5BeK8n4rbY9oAJxrmKWOuImd3ZYcTj/FPdb2 jJLXFRha+Q7ERnsBZifTFijpda8XPNDI9gPItiLsvkjmbQtAsn8L1qQF4XOocbXXc8zc lOGg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=WxJtcfmjg8bDlWo77QXfqDNdo8CBClhx9W/RQtlqbwY=; b=G1CfitKBAzwzqCKldWUevdiYSpNqXHND222/x9zSWBqd8HRbbNyaK03Hmy0PmozWSx f4YGejQ+b9I3Yv2/42QkX/VB5HAKRoBfW5c6YsDvswqCTsFJh9FvtURBfLQz8eGfhxWN IrARyVLNLTa8ZcbroPNdu89iz7UBwMbiZ2sRtOJQoSsfn5yYia5W78oJp/3u5RtT+U2d JBbz7jLuuZAd6JuMD6Hsp8HkSGJ1GcqoaN1lkjTE9eXZfq2BfWXxWKBSRofN1lP1IPYX EipmGrr5TONJ2x3emeCrVubkYZKduJEFhCEPJNDlMXKEUd2GdgQ5iWtP6JG1LUDwV5os w1UQ== X-Gm-Message-State: AFqh2kr1tgzht9nHarHG0JapSqA9AQxPVB11tfCb8xWptWQqNvWoqo78 bSqD4eN4DO8vsuf1P83LhlXDWQ== X-Google-Smtp-Source: AMrXdXsEe/2+E0aFpK50BI2W31LvjkQnB05BvrClqgL71HBhXQ2hq9P1I+orXsNyKBoEZPHv4iTJdA== X-Received: by 2002:a9d:704f:0:b0:685:579f:918e with SMTP id x15-20020a9d704f000000b00685579f918emr6930248otj.0.1674184742349; Thu, 19 Jan 2023 19:19:02 -0800 (PST) Received: from ?IPV6:2607:fb90:f20b:1885:28a8:1eff:fe1b:3320? ([2607:fb90:f20b:1885:28a8:1eff:fe1b:3320]) by smtp.gmail.com with ESMTPSA id m6-20020a9d73c6000000b006860be3a43fsm7631822otk.14.2023.01.19.19.19.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 19 Jan 2023 19:19:01 -0800 (PST) Message-ID: <0f51dac4-836b-0ff2-38c6-5521745c1c88@landley.net> Date: Thu, 19 Jan 2023 21:31:21 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.5.0 Subject: Re: Calculating array sizes in C - was: Re: Build regressions/improvements in v6.2-rc1 Content-Language: en-US To: "Michael.Karcher" , John Paul Adrian Glaubitz , Geert Uytterhoeven References: <20221227082932.798359-1-geert@linux-m68k.org> <3800eaa8-a4da-b2f0-da31-6627176cb92e@physik.fu-berlin.de> <429140e0-72fe-c91c-53bc-124d33ab5ffa@physik.fu-berlin.de> <0d238f02-4d78-6f14-1b1b-f53f0317a910@physik.fu-berlin.de> <1732342f-49fe-c20e-b877-bc0a340e1a50@fu-berlin.de> From: Rob Landley In-Reply-To: <1732342f-49fe-c20e-b877-bc0a340e1a50@fu-berlin.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-xtensa@linux-xtensa.org, Arnd Bergmann , linux-sh@vger.kernel.org, linux-wireless@vger.kernel.org, linux-mips@vger.kernel.org, amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, Michael Karcher , linux-f2fs-devel@lists.sourceforge.net, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 1/19/23 16:11, Michael.Karcher wrote: > Isn't this supposed to be caught by this check: >>>> >>>>          a, __same_type(a, NULL) >>>> >>>> ? >>> >>> Yeah, but gcc thinks it is smarter than us... >>> Probably it drops the test, assuming UB cannot happen. >> Hmm, sounds like a GGC bug to me then. Not sure how to fix this then. > > > I don't see a clear bug at this point. We are talking about the C expression > >   __same_type((void*)0, (void*)0)? 0 : sizeof((void*)0)/sizeof(*((void*0)) *(void*) is type "void" which does not have a size. The problem is gcc "optimizing out" an earlier type check, the same way it "optimizes out" checks for signed integer math overflowing, or "optimizes out" a comparison to pointers from two different local variables from different function calls trying to calculate the amount of stack used, or "optimizes out" using char *x = (char *)1; as a flag value and then doing "if (!(x-1)) because it can "never happen"... > I suggest to file a bug against gcc complaining about a "spurious > warning", and using "-Werror -Wno-error-sizeof-pointer-div" until gcc is > adapted to not emit the warning about the pointer division if the result > is not used. Remember when gcc got rewritten in c++ starting in 2007? Historically the main marketing push of C++ was that it contains the whole of C and therefore MUST be just as good a language, the same way a mud pie contains an entire glass of water and therefore MUST be just as good a beverage. Anything C can do that C++ _can't_ do is seen as an existential threat by C++ developers. They've worked dilligently to "fix" C not being a giant pile of "undefined behavior" the way C++ is for 15 years now. I have... opinions on this. > Regards, >   Michael Karcher Rob From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C0F08C004D4 for ; Fri, 20 Jan 2023 03:20:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=R2gvlNt3wckwECtBcO9fkfAHJ4IYMSoftPstwCZfS3s=; b=11TLrXdE+WsHau 2RYiyI5h2qU7hybe5+zdH/22KlVnWf3uXRC10d7vmldBtheFdEZ+K9uDToKEqKv99CXsH48UYwiIk 2V/bwoIsTU2Z8CSjmTYfEGI0dBO/CYhaEgIGtyx1nEyrQyKAoy4YhFU8rjJTLrxt73jrEHE+spyMA sIPLIO3X6l1Ji3kiQc18neMt5Lknxn7vbDMj3IPVza2bOQDgoh4Tw6JJfFn/igPO2mdV0oByn5z3u 8qMT32XPkxwEsKdyAWIbeq7DKHwSCIVK3fynbxmZDtNW7sZZboH+PIE8hYyUlGv78SpuJ9Ga76DmJ KQn+B8y/PVIxRWYPrxZA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pIhvo-008Crl-NN; Fri, 20 Jan 2023 03:19:08 +0000 Received: from mail-ot1-x32a.google.com ([2607:f8b0:4864:20::32a]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pIhvk-008Cqt-Nz for linux-arm-kernel@lists.infradead.org; Fri, 20 Jan 2023 03:19:06 +0000 Received: by mail-ot1-x32a.google.com with SMTP id x21-20020a056830245500b006865ccca77aso2374094otr.11 for ; Thu, 19 Jan 2023 19:19:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=landley-net.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=WxJtcfmjg8bDlWo77QXfqDNdo8CBClhx9W/RQtlqbwY=; b=195AXt9odDu2myrtF32+GBb0qMFgjNikCrpxsa+WbA8hIOrugiKzMmRa6ck9jEEnh+ BAiMUjeACSwa7DIsy0nd31WMLgqeemkaP54UGh/z5/4/iE4OKfk/JF3Mfjc9Slk04hNo yl5Eob9OFP8rjo94KXNck41rTFVGwR12Dn+yA5SLoZAqZ3VzofVm+vx+0BgQAYSmr785 93R2tgLtdgq0ZrmMjpy2ltpjwYB3CfaG5BeK8n4rbY9oAJxrmKWOuImd3ZYcTj/FPdb2 jJLXFRha+Q7ERnsBZifTFijpda8XPNDI9gPItiLsvkjmbQtAsn8L1qQF4XOocbXXc8zc lOGg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=WxJtcfmjg8bDlWo77QXfqDNdo8CBClhx9W/RQtlqbwY=; b=TvMACjSDACcnH+/LReUX4F/uSLdob1WVat3nzZg7bf7c4SqXup2Q33ME/qf4lFcx55 eyeOAYbl4SqZlLdewwjXiRS6VAbL9ZrvDUaiXHKG/2RhubcgMPJgfTRi9sQfx7WFwuL2 nSvNBtO5WZU+fvAe9QY4kX+842+U4LTup0FCmJPkVVx9/BTiA+PwUnMPweS+d60kHCtE TH8zaQoYzBZJQUao59/cpGl/YhJasGYuaP7q+FvHB482FqTTlOlpiuvdicAgBBqnKk8x Gtald+uSTXjiDlLyU5aMbaH8eOn/DgPtoBBmnshwYs32CuITuVCutjzDad326ybFmOus 1NNQ== X-Gm-Message-State: AFqh2kq17jUlcTZa8+qZ8o6LCABGYMNCpEPrpD9fN84XBALb3fzl/Syt ZoENzg8v2w6EUvosKaB8zcOQgQ== X-Google-Smtp-Source: AMrXdXsEe/2+E0aFpK50BI2W31LvjkQnB05BvrClqgL71HBhXQ2hq9P1I+orXsNyKBoEZPHv4iTJdA== X-Received: by 2002:a9d:704f:0:b0:685:579f:918e with SMTP id x15-20020a9d704f000000b00685579f918emr6930248otj.0.1674184742349; Thu, 19 Jan 2023 19:19:02 -0800 (PST) Received: from ?IPV6:2607:fb90:f20b:1885:28a8:1eff:fe1b:3320? ([2607:fb90:f20b:1885:28a8:1eff:fe1b:3320]) by smtp.gmail.com with ESMTPSA id m6-20020a9d73c6000000b006860be3a43fsm7631822otk.14.2023.01.19.19.19.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 19 Jan 2023 19:19:01 -0800 (PST) Message-ID: <0f51dac4-836b-0ff2-38c6-5521745c1c88@landley.net> Date: Thu, 19 Jan 2023 21:31:21 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.5.0 Subject: Re: Calculating array sizes in C - was: Re: Build regressions/improvements in v6.2-rc1 Content-Language: en-US To: "Michael.Karcher" , John Paul Adrian Glaubitz , Geert Uytterhoeven Cc: linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-wireless@vger.kernel.org, linux-mips@vger.kernel.org, linux-sh@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linuxppc-dev@lists.ozlabs.org, kasan-dev@googlegroups.com, linux-xtensa@linux-xtensa.org, Michael Karcher , Arnd Bergmann References: <20221227082932.798359-1-geert@linux-m68k.org> <3800eaa8-a4da-b2f0-da31-6627176cb92e@physik.fu-berlin.de> <429140e0-72fe-c91c-53bc-124d33ab5ffa@physik.fu-berlin.de> <0d238f02-4d78-6f14-1b1b-f53f0317a910@physik.fu-berlin.de> <1732342f-49fe-c20e-b877-bc0a340e1a50@fu-berlin.de> From: Rob Landley In-Reply-To: <1732342f-49fe-c20e-b877-bc0a340e1a50@fu-berlin.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230119_191905_038670_79A9990B X-CRM114-Status: GOOD ( 15.39 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; 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([2607:fb90:f20b:1885:28a8:1eff:fe1b:3320]) by smtp.gmail.com with ESMTPSA id m6-20020a9d73c6000000b006860be3a43fsm7631822otk.14.2023.01.19.19.19.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 19 Jan 2023 19:19:01 -0800 (PST) Message-ID: <0f51dac4-836b-0ff2-38c6-5521745c1c88@landley.net> Date: Thu, 19 Jan 2023 21:31:21 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.5.0 Content-Language: en-US To: "Michael.Karcher" , John Paul Adrian Glaubitz , Geert Uytterhoeven References: <20221227082932.798359-1-geert@linux-m68k.org> <3800eaa8-a4da-b2f0-da31-6627176cb92e@physik.fu-berlin.de> <429140e0-72fe-c91c-53bc-124d33ab5ffa@physik.fu-berlin.de> <0d238f02-4d78-6f14-1b1b-f53f0317a910@physik.fu-berlin.de> <1732342f-49fe-c20e-b877-bc0a340e1a50@fu-berlin.de> From: Rob Landley In-Reply-To: <1732342f-49fe-c20e-b877-bc0a340e1a50@fu-berlin.de> X-Headers-End: 1pIj0c-009qSz-ME Subject: Re: [f2fs-dev] Calculating array sizes in C - was: Re: Build regressions/improvements in v6.2-rc1 X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-xtensa@linux-xtensa.org, Arnd Bergmann , linux-sh@vger.kernel.org, linux-wireless@vger.kernel.org, linux-mips@vger.kernel.org, amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, Michael Karcher , linux-f2fs-devel@lists.sourceforge.net, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net CgpPbiAxLzE5LzIzIDE2OjExLCBNaWNoYWVsLkthcmNoZXIgd3JvdGU6Cj4gSXNuJ3QgdGhpcyBz dXBwb3NlZCB0byBiZSBjYXVnaHQgYnkgdGhpcyBjaGVjazoKPj4+Pgo+Pj4+IMKgwqDCoMKgwqDC oMKgwqAgYSwgX19zYW1lX3R5cGUoYSwgTlVMTCkKPj4+Pgo+Pj4+ID8KPj4+Cj4+PiBZZWFoLCBi dXQgZ2NjIHRoaW5rcyBpdCBpcyBzbWFydGVyIHRoYW4gdXMuLi4KPj4+IFByb2JhYmx5IGl0IGRy b3BzIHRoZSB0ZXN0LCBhc3N1bWluZyBVQiBjYW5ub3QgaGFwcGVuLgo+PiBIbW0sIHNvdW5kcyBs aWtlIGEgR0dDIGJ1ZyB0byBtZSB0aGVuLiBOb3Qgc3VyZSBob3cgdG8gZml4IHRoaXMgdGhlbi4K PiAKPiAKPiBJIGRvbid0IHNlZSBhIGNsZWFyIGJ1ZyBhdCB0aGlzIHBvaW50LiBXZSBhcmUgdGFs a2luZyBhYm91dCB0aGUgQyBleHByZXNzaW9uCj4gCj4gIMKgIF9fc2FtZV90eXBlKCh2b2lkKikw LCAodm9pZCopMCk/IDAgOiBzaXplb2YoKHZvaWQqKTApL3NpemVvZigqKCh2b2lkKjApKQoKKih2 b2lkKikgaXMgdHlwZSAidm9pZCIgd2hpY2ggZG9lcyBub3QgaGF2ZSBhIHNpemUuCgpUaGUgcHJv YmxlbSBpcyBnY2MgIm9wdGltaXppbmcgb3V0IiBhbiBlYXJsaWVyIHR5cGUgY2hlY2ssIHRoZSBz YW1lIHdheSBpdAoib3B0aW1pemVzIG91dCIgY2hlY2tzIGZvciBzaWduZWQgaW50ZWdlciBtYXRo IG92ZXJmbG93aW5nLCBvciAib3B0aW1pemVzIG91dCIgYQpjb21wYXJpc29uIHRvIHBvaW50ZXJz IGZyb20gdHdvIGRpZmZlcmVudCBsb2NhbCB2YXJpYWJsZXMgZnJvbSBkaWZmZXJlbnQKZnVuY3Rp b24gY2FsbHMgdHJ5aW5nIHRvIGNhbGN1bGF0ZSB0aGUgYW1vdW50IG9mIHN0YWNrIHVzZWQsIG9y ICJvcHRpbWl6ZXMgb3V0Igp1c2luZyBjaGFyICp4ID0gKGNoYXIgKikxOyBhcyBhIGZsYWcgdmFs dWUgYW5kIHRoZW4gZG9pbmcgImlmICghKHgtMSkpIGJlY2F1c2UKaXQgY2FuICJuZXZlciBoYXBw ZW4iLi4uCj4gSSBzdWdnZXN0IHRvIGZpbGUgYSBidWcgYWdhaW5zdCBnY2MgY29tcGxhaW5pbmcg YWJvdXQgYSAic3B1cmlvdXMgCj4gd2FybmluZyIsIGFuZCB1c2luZyAiLVdlcnJvciAtV25vLWVy cm9yLXNpemVvZi1wb2ludGVyLWRpdiIgdW50aWwgZ2NjIGlzIAo+IGFkYXB0ZWQgdG8gbm90IGVt aXQgdGhlIHdhcm5pbmcgYWJvdXQgdGhlIHBvaW50ZXIgZGl2aXNpb24gaWYgdGhlIHJlc3VsdCAK PiBpcyBub3QgdXNlZC4KClJlbWVtYmVyIHdoZW4gZ2NjIGdvdCByZXdyaXR0ZW4gaW4gYysrIHN0 YXJ0aW5nIGluIDIwMDc/CgpIaXN0b3JpY2FsbHkgdGhlIG1haW4gbWFya2V0aW5nIHB1c2ggb2Yg QysrIHdhcyB0aGF0IGl0IGNvbnRhaW5zIHRoZSB3aG9sZSBvZiBDCmFuZCB0aGVyZWZvcmUgTVVT VCBiZSBqdXN0IGFzIGdvb2QgYSBsYW5ndWFnZSwgdGhlIHNhbWUgd2F5IGEgbXVkIHBpZSBjb250 YWlucwphbiBlbnRpcmUgZ2xhc3Mgb2Ygd2F0ZXIgYW5kIHRoZXJlZm9yZSBNVVNUIGJlIGp1c3Qg YXMgZ29vZCBhIGJldmVyYWdlLiBBbnl0aGluZwpDIGNhbiBkbyB0aGF0IEMrKyBfY2FuJ3RfIGRv IGlzIHNlZW4gYXMgYW4gZXhpc3RlbnRpYWwgdGhyZWF0IGJ5IEMrKyBkZXZlbG9wZXJzLgpUaGV5 J3ZlIHdvcmtlZCBkaWxsaWdlbnRseSB0byAiZml4IiBDIG5vdCBiZWluZyBhIGdpYW50IHBpbGUg b2YgInVuZGVmaW5lZApiZWhhdmlvciIgdGhlIHdheSBDKysgaXMgZm9yIDE1IHllYXJzIG5vdy4K CkkgaGF2ZS4uLiBvcGluaW9ucyBvbiB0aGlzLgoKPiBSZWdhcmRzLAo+ICDCoCBNaWNoYWVsIEth cmNoZXIKClJvYgoKCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fCkxpbnV4LWYyZnMtZGV2ZWwgbWFpbGluZyBsaXN0CkxpbnV4LWYyZnMtZGV2ZWxAbGlzdHMu c291cmNlZm9yZ2UubmV0Cmh0dHBzOi8vbGlzdHMuc291cmNlZm9yZ2UubmV0L2xpc3RzL2xpc3Rp bmZvL2xpbnV4LWYyZnMtZGV2ZWwK