From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by sourceware.org (Postfix) with ESMTPS id F2F1938930D5 for ; Fri, 24 Apr 2020 11:08:23 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org F2F1938930D5 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=tdevries@suse.de X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 2B56FAF6E; Fri, 24 Apr 2020 11:08:22 +0000 (UTC) Subject: Re: [PATCH] Fix inline frame unwinding breakage To: Luis Machado , Andrew Burgess Cc: tromey@adacore.com, gdb-patches@sourceware.org References: <20200414213137.24015-1-luis.machado@linaro.org> <20200414213836.24370-1-luis.machado@linaro.org> <20200422093723.GA3522@embecosm.com> <9722a14e-83af-03c6-b120-aac9816f9fc9@linaro.org> <12f56c2f-5d1f-9f98-e91a-762e76018966@suse.de> From: Tom de Vries Autocrypt: addr=tdevries@suse.de; keydata= xsBNBF0ltCcBCADDhsUnMMdEXiHFfqJdXeRvgqSEUxLCy/pHek88ALuFnPTICTwkf4g7uSR7 HvOFUoUyu8oP5mNb4VZHy3Xy8KRZGaQuaOHNhZAT1xaVo6kxjswUi3vYgGJhFMiLuIHdApoc u5f7UbV+egYVxmkvVLSqsVD4pUgHeSoAcIlm3blZ1sDKviJCwaHxDQkVmSsGXImaAU+ViJ5l CwkvyiiIifWD2SoOuFexZyZ7RUddLosgsO0npVUYbl6dEMq2a5ijGF6/rBs1m3nAoIgpXk6P TCKlSWVW6OCneTaKM5C387972qREtiArTakRQIpvDJuiR2soGfdeJ6igGA1FZjU+IsM5ABEB AAHNH1RvbSBkZSBWcmllcyA8dGRldnJpZXNAc3VzZS5kZT7CwKsEEwEIAD4WIQSsnSe5hKbL MK1mGmjuhV2rbOJEoAUCXSW0JwIbAwUJA8JnAAULCQgHAgYVCgkICwIEFgIDAQIeAQIXgAAh CRDuhV2rbOJEoBYhBKydJ7mEpsswrWYaaO6FXats4kSgc48H/Ra2lq5p3dHsrlQLqM7N68Fo eRDf3PMevXyMlrCYDGLVncQwMw3O/AkousktXKQ42DPJh65zoXB22yUt8m0g12xkLax98KFJ 5NyUloa6HflLl+wQL/uZjIdNUQaHQLw3HKwRMVi4l0/Jh/TygYG1Dtm8I4o708JS4y8GQxoQ UL0z1OM9hyM3gI2WVTTyprsBHy2EjMOu/2Xpod95pF8f90zBLajy6qXEnxlcsqreMaqmkzKn 3KTZpWRxNAS/IH3FbGQ+3RpWkNGSJpwfEMVCeyK5a1n7yt1podd1ajY5mA1jcaUmGppqx827 8TqyteNe1B/pbiUt2L/WhnTgW1NC1QDOwE0EXSW0JwEIAM99H34Bu4MKM7HDJVt864MXbx7B 1M93wVlpJ7Uq+XDFD0A0hIal028j+h6jA6bhzWto4RUfDl/9mn1StngNVFovvwtfzbamp6+W pKHZm9X5YvlIwCx131kTxCNDcF+/adRW4n8CU3pZWYmNVqhMUiPLxElA6QhXTtVBh1RkjCZQ Kmbd1szvcOfaD8s+tJABJzNZsmO2hVuFwkDrRN8Jgrh92a+yHQPd9+RybW2l7sJv26nkUH5Z 5s84P6894ebgimcprJdAkjJTgprl1nhgvptU5M9Uv85Pferoh2groQEAtRPlCGrZ2/2qVNe9 XJfSYbiyedvApWcJs5DOByTaKkcAEQEAAcLAkwQYAQgAJhYhBKydJ7mEpsswrWYaaO6FXats 4kSgBQJdJbQnAhsMBQkDwmcAACEJEO6FXats4kSgFiEErJ0nuYSmyzCtZhpo7oVdq2ziRKD3 twf7BAQBZ8TqR812zKAD7biOnWIJ0McV72PFBxmLIHp24UVe0ZogtYMxSWKLg3csh0yLVwc7 H3vldzJ9AoK3Qxp0Q6K/rDOeUy3HMqewQGcqrsRRh0NXDIQk5CgSrZslPe47qIbe3O7ik/MC q31FNIAQJPmKXX25B115MMzkSKlv4udfx7KdyxHrTSkwWZArLQiEZj5KG4cCKhIoMygPTA3U yGaIvI/BGOtHZ7bEBVUCFDFfOWJ26IOCoPnSVUvKPEOH9dv+sNy7jyBsP5QxeTqwxC/1ZtNS DUCSFQjqA6bEGwM22dP8OUY6SC94x1G81A9/xbtm9LQxKm0EiDH8KBMLfQ== Message-ID: <20452d56-2189-1b67-6df0-ea26c7402a91@suse.de> Date: Fri, 24 Apr 2020 13:08:21 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-16.2 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, 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: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 Apr 2020 11:08:25 -0000 On 24-04-2020 12:58, Luis Machado wrote: > On 4/24/20 7:02 AM, Luis Machado wrote: >> On 4/24/20 6:17 AM, Tom de Vries wrote: >>> On 23-04-2020 19:51, Luis Machado via Gdb-patches wrote: >>>> On 4/22/20 8:22 AM, Luis Machado wrote: >>>>> Hi Andrew, >>>>> >>>>> On 4/22/20 6:37 AM, Andrew Burgess wrote: >>>>>> * Luis Machado via Gdb-patches >>>>>> [2020-04-14 18:38:36 -0300]: >>>>>> >>>>>>> *** re-sending due to the poor choice of characters for the >>>>>>> backtrace >>>>>>> annotations. GIT swallowed parts of it. >>>>>>> >>>>>>> There has been some breakage for aarch64-linux, arm-linux and >>>>>>> s390-linux in >>>>>>> terms of inline frame unwinding. There may be other targets, but >>>>>>> these are >>>>>>> the ones i'm aware of. >>>>>>> >>>>>>> The following testcases started to show numerous failures and >>>>>>> trigger internal >>>>>>> errors in GDB after commit 1009d92fc621bc4d017029b90a5bfab16e17fde5, >>>>>>> "Find tailcall frames before inline frames". >>>>>>> >>>>>>> gdb.opt/inline-break.exp >>>>>>> gdb.opt/inline-cmds.exp >>>>>>> gdb.python/py-frame-inline.exp >>>>>>> gdb.reverse/insn-reverse.exp >>>>>>> >>>>>>> The internal errors were of this kind: >>>>>>> >>>>>>> binutils-gdb/gdb/frame.c:579: internal-error: frame_id >>>>>>> get_frame_id(frame_info*): Assertion `fi->level == 0' failed. >>>>>> >>>>>> I have also started seeing this assert on RISC-V, and your patch >>>>>> resolves this issue for me, so I'm keen to see this merged. >>>>> >>>>> Great. >>>>> >>>>>> >>>>>> I took a look through and it all looks good to me - is there anything >>>>>> holding this back from being merged? >>>>> >>>>> Not really. I was waiting for an OK before pushing it. >>>>> >>>>>> >>>>>> Thanks, >>>>>> Andrew >>>> >>>> I've pushed this now. Tromey and Andrew OK-ed it on IRC. >>> >>> This causes at least: >>> ... >>> FAIL: gdb.arch/amd64-entry-value.exp: tailcall: bt >>> FAIL: gdb.arch/amd64-entry-value.exp: tailcall: p i >>> FAIL: gdb.arch/amd64-entry-value.exp: tailcall: p i@entry >>> FAIL: gdb.arch/amd64-entry-value.exp: tailcall: p j >>> FAIL: gdb.arch/amd64-entry-value.exp: tailcall: p j@entry >>> FAIL: gdb.arch/amd64-entry-value.exp: p $sp0 == $sp >>> FAIL: gdb.arch/amd64-entry-value.exp: frame 3 >>> FAIL: gdb.arch/amd64-entry-value.exp: down >>> FAIL: gdb.arch/amd64-entry-value.exp: disassemble >>> FAIL: gdb.arch/amd64-entry-value.exp: ambiguous: bt >>> FAIL: gdb.arch/amd64-entry-value.exp: self: bt >>> FAIL: gdb.arch/amd64-entry-value.exp: self: bt debug entry-values >>> FAIL: gdb.arch/amd64-tailcall-cxx.exp: bt >>> FAIL: gdb.arch/amd64-tailcall-noret.exp: bt >>> FAIL: gdb.arch/amd64-tailcall-self.exp: bt >>> ... >>> >>> Looking at the first FAIL, before this commit we have: >>> ... >>> (gdb) PASS: gdb.arch/amd64-entry-value.exp: continue to breakpoint: >>> tailcall: breakhere >>> bt^M >>> #0  d (i=71, i@entry=70, j=73.5, j@entry=72.5) at >>> gdb.arch/amd64-entry-value.cc:34^M >>> #1  0x00000000004006af in c (i=i@entry=7, j=j@entry=7.25) at >>> gdb.arch/amd64-entry-value.cc:47^M >>> #2  0x00000000004006cd in b (i=i@entry=5, j=j@entry=5.25) at >>> gdb.arch/amd64-entry-value.cc:59^M >>> #3  0x0000000000400524 in main () at gdb.arch/amd64-entry-value.cc:229^M >>> (gdb) PASS: gdb.arch/amd64-entry-value.exp: tailcall: bt >>> ... >>> which has now degraded into: >>> ... >>> (gdb) PASS: gdb.arch/amd64-entry-value.exp: continue to breakpoint: >>> tailcall: breakhere >>> bt^M >>> #0  d (i=, j=) at >>> gdb.arch/amd64-entry-value.cc:34^M >>> #1  0x0000000000400524 in main () at gdb.arch/amd64-entry-value.cc:229^M >>> (gdb) FAIL: gdb.arch/amd64-entry-value.exp: tailcall: bt >>> ... >>> >>> Thanks, >>> - Tom >>> >> >> I'll take a look at it. > > Just a quick update... I did a before/after run and the only regression > seems to be from gdb.arch/amd64-entry-value.exp. > > The other failures are still there even after reverting the inline frame > unwinding fix. > > I'll check what's up with the regressed test. > > Could you please confirm this when you have some cycles? Hi, I cannot confirm this. All these FAILs fail with the patch, and pass with the patch reverted. Looking at amd64-tailcall-cxx.exp, we have normally: ... (gdb) bt^M #0 g (x=x@entry=2) at gdb.arch/amd64-tailcall-cxx1.cc:23^M #1 0x00000000004004e8 in f (x=x@entry=1) at gdb.arch/amd64-tailcall-cxx2.cc:23^M #2 0x00000000004003de in main () at gdb.arch/amd64-tailcall-cxx1.cc:31^M (gdb) PASS: gdb.arch/amd64-tailcall-cxx.exp: bt ... and with the patch: ... (gdb) bt^M #0 g (x=2) at gdb.arch/amd64-tailcall-cxx1.cc:23^M #1 0x00000000004003de in main () at gdb.arch/amd64-tailcall-cxx1.cc:31^M (gdb) FAIL: gdb.arch/amd64-tailcall-cxx.exp: bt ... So, I'd say it looks very similar to the issue in gdb.arch/amd64-entry-value.exp. Thanks, - Tom