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[2003:f6:5f06:ab04::1b9]) by smtp.gmail.com with UTF8SMTPSA id a640c23a62f3a-b07b32f1edasm351368066b.89.2025.09.12.03.28.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 Sep 2025 03:28:27 -0700 (PDT) From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= To: "Gustavo A. R. Silva" , Kees Cook Cc: linux-kernel@vger.kernel.org Subject: [PATCH 0/2] stddef: Simplify TRAILING_OVERLAP() and improve docs Date: Fri, 12 Sep 2025 12:28:00 +0200 Message-ID: X-Mailer: git-send-email 2.50.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Developer-Signature: v=1; a=openpgp-sha256; l=905; i=u.kleine-koenig@baylibre.com; h=from:subject:message-id; bh=22VN1Nog80BwtvrES1R6qAU8hOqcLI3BDqyb1tefays=; b=owEBbQGS/pANAwAKAY+A+1h9Ev5OAcsmYgBow/WydnMssDJxf3PoW3NatKlaCsuUSzmqM3iYt bzbZcKMOAqJATMEAAEKAB0WIQQ/gaxpOnoeWYmt/tOPgPtYfRL+TgUCaMP1sgAKCRCPgPtYfRL+ TlLpB/9NNVV4zlGfv0G7EWGWxkmRiWddhK/nviOlOTYt9fjawGeKq2vyL4oaptlA5+19k5oTnzd 63UY/diw3YebbIKqoT4f7JvjGdR3I03s2VnxkYM5CNRyhS/vv9Be123ZZFXGeX1xu6Trd3fANzu 096JE/ysoVEIIakLwBjcwz1cr1hGvm38Zen5ZqKsDk9+iFb9+0A07z6bkZU0M2TTbEA2SFxANeH dmmaPQyLbN0ZAqfDfKbTAHigkAw7/e90hblY3rMp9wh6SvyOrcZZhdlHpeUoSVNNZaUMuL9EVSi 96tS/Pcow0G067kAPPqh8J9HTXKybNRBaMxIA1RpwY8Z2UBR X-Developer-Key: i=u.kleine-koenig@baylibre.com; a=openpgp; fpr=0D2511F322BFAB1C1580266BE2DCDD9132669BD6 Content-Transfer-Encoding: 8bit Hello, as a follup to the discussion I had with Gustavo in reply to https://lore.kernel.org/linux-pwm/aJtRPZpc-Lv-C6zD@kspp here comes my suggestion to improve TRAILING_OVERLAP() for wider audience. While working at it, I wonder if __packed should also better be part of the macro to ensure that struct myfamstruct { char c; char payload[]; }; TRAILING_OVERLAP(struct myfamstruct, mfs, payload, unsigned int payload_as_int; ) fs; does the right thing. This however is orthogonal and better discussed separately from this patch set. Best regards Uwe Uwe Kleine-König (2): stddef: Add a comment about why TRAILING_OVERLAP() exists stddef: Stop using FAM parameter of TRAILING_OVERLAP() include/linux/stddef.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585 -- 2.50.1