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 mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7DF2DCD5BD1 for ; Tue, 2 Jun 2026 22:30:30 +0000 (UTC) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 6C95B402B6; Wed, 3 Jun 2026 00:30:29 +0200 (CEST) Received: from inbox.dpdk.org (inbox.dpdk.org [95.142.172.178]) by mails.dpdk.org (Postfix) with ESMTP id 95B66402A9 for ; Wed, 3 Jun 2026 00:30:27 +0200 (CEST) Received: by inbox.dpdk.org (Postfix, from userid 33) id 8381F4B5B0; Wed, 3 Jun 2026 00:30:27 +0200 (CEST) From: bugzilla@dpdk.org To: dev@dpdk.org Subject: [DPDK/core Bug 1949] function versioning is incompatible with LTO Date: Tue, 02 Jun 2026 22:30:27 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: DPDK X-Bugzilla-Component: core X-Bugzilla-Version: 25.07 X-Bugzilla-Keywords: X-Bugzilla-Severity: minor X-Bugzilla-Who: stephen@networkplumber.org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: Normal X-Bugzilla-Assigned-To: dev@dpdk.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter target_milestone Message-ID: Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 X-Bugzilla-URL: http://bugs.dpdk.org/ Auto-Submitted: auto-generated X-Auto-Response-Suppress: All MIME-Version: 1.0 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org http://bugs.dpdk.org/show_bug.cgi?id=3D1949 Bug ID: 1949 Summary: function versioning is incompatible with LTO Product: DPDK Version: 25.07 Hardware: All OS: All Status: UNCONFIRMED Severity: minor Priority: Normal Component: core Assignee: dev@dpdk.org Reporter: stephen@networkplumber.org Target Milestone: --- The default-version symver (@@) fails to assemble when build is using LTO. Building a shared library with LTO fails when a function uses RTE_DEFAULT_SYMBOL. I introduces a new versioned symbol rte_eth_dev_get_name_by_port (ethdev). This fails when doing LTO build with invalid attempt to declare external version name as default in symbol `rte_eth_dev_get_name_by_port@@DPDK_27' Cause: the versioning macros emit a file-scope __asm__(".symver =E2=80=A6@@DPDK_"). Top-level asm is opaque to LTO, so GCC may place t= he directive in a different ltrans partition than the _v definition. The implementa= tion symbol is then external in that partition, and gas rejects binding a default version (@@) to an external symbol. Only the @@ (default) line fails; the single-@ compat line is legal on an external symbol. Fix: use the GCC symver function attribute (GCC =E2=89=A5 10) instead of to= p-level asm, gated on __has_attribute(symver); retain the asm path as fallback. Clang la= cks the attribute and stays on the asm path (LTO + versioning remains unsupport= ed there). Marking severity as minor since no current in-tree code uses versioned symb= ols. But it is a trap waiting to happen. --=20 You are receiving this mail because: You are the assignee for the bug.=