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Tue, 28 Apr 2026 10:28:55 -0600 From: Tom Tromey To: Simon Marchi Cc: gdb-patches@sourceware.org, Simon Marchi Subject: Re: [PATCH 09/11] gdb: add objfile -> solib backlink In-Reply-To: <20251209193610.296085-10-simon.marchi@efficios.com> (Simon Marchi's message of "Tue, 9 Dec 2025 14:32:13 -0500") References: <20251209193610.296085-1-simon.marchi@efficios.com> <20251209193610.296085-10-simon.marchi@efficios.com> X-Attribution: Tom Date: Tue, 28 Apr 2026 10:28:54 -0600 Message-ID: <87o6j3kq0p.fsf@tromey.com> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - box5379.bluehost.com X-AntiAbuse: Original Domain - sourceware.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - tromey.com X-BWhitelist: no X-Source-IP: 75.166.225.82 X-Source-L: No X-Exim-ID: 1wHlIt-00000003acW-2JqU X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 75-166-225-82.hlrn.qwest.net (bapiya) [75.166.225.82]:38736 X-Source-Auth: tom+tromey.com X-Email-Count: 18 X-Org: HG=bhshared;ORG=bluehost; X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes X-CMAE-Envelope: MS4xfH4MLvE5rIT1iOMDJwoGvtxWVdzv/1e0WXpoTQqanWIB0v43kQX2s9xvcnix6RQVFAJFiBMXIfbf/V/UKYIj8LeiEkFSgGjOm/i4X+LudM+nip1O+Wmp UlALTXGXwtuUXzxixASxr23pJ1JKZtCVr5IR1AhXpsB048YpV3XErK2mf8iVZ45Li/bBFzHnG1JrQjiIOMT5YMzV+MF0dDFQwlY= X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: gdb-patches-bounces~public-inbox=simark.ca@sourceware.org >>>>> "Simon" == Simon Marchi writes: Simon> However, I learned that there may be more than one solib linked to one Simon> objfile, so this backlink is actually a vector. How / when can this happen? It seems surprising to me, except maybe for separate debug info. Simon> @@ -732,10 +733,14 @@ remove_solib (program_space *pspace, Simon> notify_solib_unloaded (pspace, *solib_it, still_in_use, false); Simon> /* Unless the user loaded it explicitly, free SO's objfile. */ Simon> - if (solib_it->objfile != nullptr Simon> - && !(solib_it->objfile->flags & OBJF_USERLOADED) Simon> - && !still_in_use) Simon> - solib_it->objfile->unlink (); Simon> + if (solib_it->objfile != nullptr) Simon> + { Simon> + /* Remove the objfile -> solib backlink. */ Simon> + solib_it->objfile->remove_solib (*solib_it); Simon> + Simon> + if (!(solib_it->objfile->flags & OBJF_USERLOADED) && !still_in_use) Simon> + solib_it->objfile->unlink (); Simon> + } Doesn't this mean that if one solib is removed, then other solibs with the same objfile will have a dangling objfile pointer? Tom