Re: [PATCH stable 6.1 0/3] perf build fixes

From: Sasha Levin

Date: Wed May 20 2026 - 10:42:27 EST


> This patch series contains "perf" build fixes specific to 6.1. We have
> seen occasional build failures in our CI looking like these:
[...]
> Ian Rogers (3):
> perf build: Conditionally define NDEBUG
> perf parse-events: Make YYDEBUG dependent on doing a debug build
> perf build: Disable fewer bison warnings

Thanks for the series.

Patch 3/3 (ddc8e4c96692) has an upstream Fixes: follow-up,
878460e8d0ff8 ("perf build: Remove -Wno-unused-but-set-variable from
the flex flags when building with clang < 13.0.0"), which we need on
6.1 alongside 3/3 to keep clang<13 perf builds working. Without it,
3/3 unconditionally adds -Wno-unused-but-set-variable and drops the
-Wno-unknown-warning-option guard that was previously gated by
BISON_GE_35, so clang 11/12 fails under WERROR=1.

878460e8d0ff8 does not cherry-pick cleanly onto 6.1 - it references
the 'version-lt3' make macro (introduced by a9b451509565d, not in 6.1)
and bpf-filter-flex.o (no such file in 6.1's tools/perf). I wasn't
comfortable resolving that conflict blind on a 6.1-only perf change.

Could you send a v2 6.1 series that includes 878460e8d0ff8 adapted to
6.1 (or an equivalent 6.1-specific patch that preserves the
-Wno-unknown-warning-option guard for clang<13)? I'll queue the whole
thing once that piece is in.

--
Thanks,
Sasha