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From: Vincent Mailhol <mailhol@kernel.org>
To: Nathan Chancellor <nathan@kernel.org>,
	Nicolas Schier <nsc@kernel.org>,
	 Nick Desaulniers <nick.desaulniers+lkml@gmail.com>,
	 Bill Wendling <morbo@google.com>,
	Justin Stitt <justinstitt@google.com>,
	 Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	 Maxime Ripard <mripard@kernel.org>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	 David Airlie <airlied@gmail.com>,
	Simona Vetter <simona@ffwll.ch>,  Chris Mason <clm@fb.com>,
	David Sterba <dsterba@suse.com>,  Kees Cook <kees@kernel.org>,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	 linux-kbuild@vger.kernel.org, linux-sparse@vger.kernel.org,
	 linux-kernel@vger.kernel.org, llvm@lists.linux.dev,
	 dri-devel@lists.freedesktop.org, linux-btrfs@vger.kernel.org,
	 linux-hardening@vger.kernel.org,
	Vincent Mailhol <mailhol@kernel.org>
Subject: [PATCH v3 0/3] kbuild: remove gcc's -Wtype-limits
Date: Sat, 20 Dec 2025 12:02:18 +0100	[thread overview]
Message-ID: <20251220-remove_wtype-limits-v3-0-24b170af700e@kernel.org> (raw)

I often read on the mailing list people saying "who cares about W=2
builds anyway?". At least I do. Not that I want to fix all of them,
but on some occasions, such as new driver submissions, I have often
found a couple valid diagnostics in the W=2 output.

That said, the annoying thing is that W=2 is heavily polluted by one
warning: -Wtype-limits. Try a gcc W=2 build on any file and see the
results for yourself. I suspect this to be the reason why so few
people are using W=2.

This series removes gcc's -Wtype-limits in an attempt to make W=2 more
useful. Those who do not use W=2 can continue to not use it if they
want. Those who, like me, use it for time to time will get an improved
experience from the reduced spam.

Patch #1 deactivates -Wtype-limits.  Extra details on statistics, past
attempts and alternatives are given in the description.

Patch #2 clean-ups the local kbuild -Wno-type-limits exceptions, while
patch #3 undoes a local workaround which silenced that warning by
uglifying the code.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
---
Changes in v3:

  - Remove patch #4.

Link to v2: https://lore.kernel.org/r/20251219-remove_wtype-limits-v2-0-2e92b3f566c5@kernel.org

Changes in v2:

  - Add two more patches to clean up some -Wtype-limits workarounds
  - Collect the Reviewed-by tags.

Link to v1: https://lore.kernel.org/r/20251218-remove_wtype-limits-v1-0-735417536787@kernel.org

---
Vincent Mailhol (3):
      kbuild: remove gcc's -Wtype-limits
      kbuild: cleanup local -Wno-type-limits exceptions
      overflow: Remove is_non_negative() and is_negative()

 drivers/gpu/drm/Makefile |  1 -
 fs/btrfs/Makefile        |  1 -
 include/linux/overflow.h | 10 ++--------
 scripts/Makefile.warn    |  4 +++-
 4 files changed, 5 insertions(+), 11 deletions(-)
---
base-commit: 3e7f562e20ee87a25e104ef4fce557d39d62fa85
change-id: 20251205-remove_wtype-limits-c77eb46d09c2

Best regards,
-- 
Vincent Mailhol <mailhol@kernel.org>


             reply	other threads:[~2025-12-20 11:03 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-12-20 11:02 Vincent Mailhol [this message]
2025-12-20 11:02 ` [PATCH v3 1/3] kbuild: remove gcc's -Wtype-limits Vincent Mailhol
2025-12-20 11:02 ` [PATCH v3 2/3] kbuild: cleanup local -Wno-type-limits exceptions Vincent Mailhol
2025-12-20 12:53   ` Nicolas Schier
2025-12-20 11:02 ` [PATCH v3 3/3] overflow: Remove is_non_negative() and is_negative() Vincent Mailhol
2025-12-20 12:52   ` Nicolas Schier
2025-12-22 10:03   ` kernel test robot
2025-12-22 18:39     ` Vincent Mailhol
2025-12-22 19:55   ` kernel test robot
2025-12-25  6:04   ` kernel test robot
2025-12-27  8:49   ` kernel test robot
2025-12-28  1:41   ` kernel test robot
2026-01-01 15:10   ` Vincent Mailhol
2026-01-01 19:39     ` Nicolas Schier
2026-01-02 11:04       ` Miguel Ojeda
2026-01-02 22:26         ` Vincent Mailhol
2026-01-02 22:29           ` [PATCH] overflow: Update is_non_negative() and is_negative() comment Vincent Mailhol
2026-01-03 10:02             ` Dan Carpenter
2026-01-03 11:10               ` Vincent Mailhol
2026-01-03 16:56                 ` Dan Carpenter
2026-01-03 19:40                   ` Vincent Mailhol
2026-01-05  7:26                     ` Dan Carpenter
2026-01-05 23:56 ` [PATCH v3 0/3] kbuild: remove gcc's -Wtype-limits Nathan Chancellor

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