Re: [PATCH v1 1/4] tools/rtla: Consolidate nr_cpus usage across all tools
From: Crystal Wood <hidden>
Date: 2026-01-05 22:24:54
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On Wed, 2025-12-17 at 10:06 +0100, Tomas Glozar wrote:
út 16. 12. 2025 v 15:41 odesílatel Tomas Glozar [off-list ref] napsal:quoted
Since commit 2f3172f9dd58c ("tools/rtla: Consolidate code between osnoise/timerlat and hist/top") that was merged into 6.18, common.h includes timerlat_u.h. Your change thus causes a double include of timerlat_u.h, leading to a build error: In file included from src/timerlat_u.c:20: src/timerlat_u.h:6:8: error: redefinition of ‘struct timerlat_u_params’ 6 | struct timerlat_u_params { | ^~~~~~~~~~~~~~~~~ In file included from src/common.h:5, from src/timerlat_u.c:19: src/timerlat_u.h:6:8: note: originally defined here 6 | struct timerlat_u_params { | ^~~~~~~~~~~~~~~~~ Please rebase your patchset and fix this so that timerlat_u.h is only included once.Correction: the base of the patchset has nothing to do with this. It is the C standard, from C23 (default in GCC 15), redefinition of structs is allowed [1], so this error doesn't exist. In earlier standards, this is not allowed. [1] https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2863.pdf
Regardless of how permissive the language might be getting in this case, we should have #pragma once on all of the headers to avoid this sort of problem. -Crystal