From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id gkm3GvKqYGA/KgAAWB0awg (envelope-from ) for ; Sun, 28 Mar 2021 12:12:34 -0400 Received: by simark.ca (Postfix, from userid 112) id 539C21E939; Sun, 28 Mar 2021 12:12:34 -0400 (EDT) X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-0.7 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,RDNS_DYNAMIC,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (ip-8-43-85-97.sourceware.org [8.43.85.97]) (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 simark.ca (Postfix) with ESMTPS id 90E681E01F for ; Sun, 28 Mar 2021 12:12:33 -0400 (EDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 4A16C385703C; Sun, 28 Mar 2021 16:12:33 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 4A16C385703C DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1616947953; bh=9qAaUeJz1qgbF4HEmEkabEDTvGTOoQgYbIyj60SSqfA=; h=Subject:To:References:Date:In-Reply-To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=RB/OKkqKvz8uUZR8C0JN6FCN23Yt2fQ1O3UIs6zjYBnGFenV+HdegSnipdcipC9R9 mKDocVgjTP+g5mdsAMu0kqm4Oru0RSpvv2IbEDkuSzhoXDLPKXZ6nfs4OLsfbF3NJ+ ZHeysfKSp0N2XUE/yo7GG5plgGmRQVAyetDKI69c= Received: from smtp.polymtl.ca (smtp.polymtl.ca [132.207.4.11]) by sourceware.org (Postfix) with ESMTPS id 44944385703C for ; Sun, 28 Mar 2021 16:12:31 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 44944385703C Received: from simark.ca (simark.ca [158.69.221.121]) (authenticated bits=0) by smtp.polymtl.ca (8.14.7/8.14.7) with ESMTP id 12SGBMO6030161 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 28 Mar 2021 12:11:28 -0400 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp.polymtl.ca 12SGBMO6030161 Received: from [10.0.0.11] (192-222-157-6.qc.cable.ebox.net [192.222.157.6]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id B8EF51E01F; Sun, 28 Mar 2021 12:11:22 -0400 (EDT) Subject: Re: [PATCH v3] [PR gdb/27614] gdb-add-index fails on symlinks. To: Lancelot SIX , gdb-patches@sourceware.org References: <20210327172758.30356-1-lsix@lancelotsix.com> Message-ID: <981b48ee-133a-7f06-9e5d-d1c331f360d1@polymtl.ca> Date: Sun, 28 Mar 2021 12:11:22 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210327172758.30356-1-lsix@lancelotsix.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Poly-FromMTA: (simark.ca [158.69.221.121]) at Sun, 28 Mar 2021 16:11:23 +0000 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: , From: Simon Marchi via Gdb-patches Reply-To: Simon Marchi Errors-To: gdb-patches-bounces@sourceware.org Sender: "Gdb-patches" On 2021-03-27 1:27 p.m., Lancelot SIX via Gdb-patches wrote: > Since V2: > - Use GDB to follow symlink instead of readlink. Unlike > readlink, GDB is guaranteed to be available. > > Since V1: > - Replace '&>/dev/null' with '>/dev/null 2>&1' > > -- > > PR 27614 shows that gdb-add-index fails to generate the index when its > argument is a symlink. > > The following one liner illustrates the reported problem: > > $ echo 'int main(){}'|gcc -g -x c -;ln -s a.out symlink;gdb-add-index symlink > gdb-add-index: No index was created for symlink > gdb-add-index: [Was there no debuginfo? Was there already an index?] > $ ls -l > -rwxr-xr-x 1 25712 Mar 19 23:05 a.out* > -rw------- 1 8277 Mar 19 23:05 a.out.gdb-index > lrwxrwxrwx 1 5 Mar 19 23:05 symlink -> a.out* > > GDB generates the .gdb-index file with a name that matches the name of > the actual program (a.out.gdb-index here), not the symlink that > references it. The remaining of the script is looking for a file named > after the provided argument (would be 'symlink.gdb-index' in our > example). > > The common option to solve such issue would be to use readlink to follow > the symlink. Unfortunately, this command is not available in the POSIX > standard. This commit therefore proposes to use GDB itself to identify > where the symlink points to. This requires some parsing of GDB output. > The added test should be enough to detect regression if GDB where to > change the way it formats its output. I preferred your previous approach, compared to relying on a maintenance command. Relying on a maintenance command is fine in tests, for example, but here somebody could use gdb-add-index from a given GDB version with a GDB of a different version. GDB=/my/newer/gdb gdb-add-index a.out In the previous review, you said: >> Would it work with just `readlink `? > This would fail if $file is a symlink to a symlink. This is what > ldconfig usually does (libfoo.so -> libfoo.so.x -> libfoo.so.x.y). Can't you just call it in a loop then? while file is a symlink: file=readlink $file Simon