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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C9AA01061B20 for ; Mon, 30 Mar 2026 21:09:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=zlsVcWSeeIpbPnsSYMwOt0k3yfDPRs+s8ihr0jHypXY=; b=OjQY0EOrF4PeVx+HTMTgxEOlnQ z9K2i47svWa22WB6zntpKPzbfo7isGkvUhRnzVU3RQZMWxh8X4DnlyMSYw8bXuGqdm/iybPris69k I+VAaJh06QJY9N0ZuIOcq8Kwi+ZasBmh6CSOooWo4n20+vFw0QHolRDXpjIAmCeig043rrdWPIOOX g5+XuRTuY1Y8jIqHYqg42gqRKEmAW8XWgphL7zNcpjwXTEHalRE/1wRuGFPncI0TqY9AcPnr+oXPX 2qJ0fCDbvHEmBIxCHoEy+yZ3OkNjOBQ3OMMdcF0R/YudO0kK3/wcGjtQDjFdiiUxnqBny89pTvnQz e7aX0bTw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w7JrM-0000000BtAm-2xqh; Mon, 30 Mar 2026 21:09:20 +0000 Received: from mail-vk1-xa29.google.com ([2607:f8b0:4864:20::a29]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1w7JrJ-0000000Bt9G-3ZRG for linux-arm-kernel@lists.infradead.org; Mon, 30 Mar 2026 21:09:18 +0000 Received: by mail-vk1-xa29.google.com with SMTP id 71dfb90a1353d-56a9c5cb48bso1956325e0c.0 for ; Mon, 30 Mar 2026 14:09:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1774904956; x=1775509756; darn=lists.infradead.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=zlsVcWSeeIpbPnsSYMwOt0k3yfDPRs+s8ihr0jHypXY=; b=EZwA6/ua8aWp8U89w0Uaq1+YR7XRPVIPXSlf8ZQYEokpKwBmoz15lAbzdk1tOAjeeO 6fYC2BH3rITBQ53fft+z/p68XiWxUDHrwSp+g9+M93rwVBkp5xPe1v+tqeEDKQDvNDPM P0oi0/sAfj8b3pXCKRcFdv+ZiHvoVBVIDootoNKwdzzmVWrz0+VpOb6XNa5XUblU47Br bmRkwNN8KDO+VJl71KtiGItTf/hgVy++6kW1LrJ38tNbswZ5U8M69ZowAc3rWSnytAdc l/iueRMVVLk+NiLBKvpSLM15Q/tr1eWo3seFI1OeUfEXJX1LgcAfzkFWcVFSRmrdSE3z krMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774904956; x=1775509756; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=zlsVcWSeeIpbPnsSYMwOt0k3yfDPRs+s8ihr0jHypXY=; b=DDk07AJB7n/fXKtwG6uyij8FNYA5zDl5fdWcxxcjCrvBncHCdpr9Tx0+GafLPTFOQG HTSIJAki0/nnNWowtoX0QT7UtTZTQOOd1wd+JWmVeBqsY5e7O0En/9KxDZw+kfIv5eQf iSdVPqrFFv/3yAoXwAPvsrviY84xUDCGR/6D+pWAy7I5C6iizJ/P17JXDN6GBuZCv0UK aTIVuqs/aNsb+PvDX2W/+sWP/IzboMZKa95djOHlgOCgmy55lpTYJcaa1NCte/4lkbDk Bf0vDbh4WnCk1oAS+HUhXlaT7kcS/fBlAhObjzbFQudz6Qyok6XIfFXdKb3gB7k6J1Fx ddYg== X-Forwarded-Encrypted: i=1; AJvYcCXSJyWKQxw19Xt8rmBSdYkXGqnXK5Z0VVHdfF1HXRrdnhjSv1nF78oEg1A9xJouLjDJFSZNlcszFw2AgonRU0YR@lists.infradead.org X-Gm-Message-State: AOJu0YzQrBFM3+dtqtZZDqt/nkig7GnGnGa+Ne9wQdBwx7y4Zf+myyvG SqalLbNfgp5h0hk+W3SpY7HHNMTr6qZCbX1K0tnm0KR3sDWWrCbNxzC+ X-Gm-Gg: ATEYQzzjjvsBVFWCjC/TqP/haP67yw8c0VtAUPdxXWI31d/T4R0KTH2IofUhm0kt+jC +huIgIyzsVIwsbAv5Tqdw2fJAYcAHG9gwsD3bINDGm8teG+l9KLIDUIQVTaKJ1jJQ5gAvKy+DLZ UpsSlzwy8oShmTPEDhyEgHathgVScoz+gmISVtpf+9cOY+H/pqXpL2rmyuesjmtmAkn+fYfSX5l Lr1LRu8RrKfuohfULT3dY/cPTrxLAI95/Y4QiCekhBTFC3GW9/ZSfxe5qkhxc5M2qKUoijrP6bx qATiKXfsqOn4XULq/griEk7dNxzoNLrdNuxm/2zwGa8fl3aGyQm+gH938r56s3KAnnEhKzJNVBF 7pjXokkFwtrWQzn+Kt8rQuuT5nRxTJjcJ/gOIEVj1Nh/ZkCHKAq27rF1vafJpaCaQ2bqKL0nkY7 j4AWztemBm1xIIOJZQrGiqsNM8VPGEHw58IjE1 X-Received: by 2002:a05:6122:3c44:b0:56b:9ba4:1372 with SMTP id 71dfb90a1353d-56d4a5f8c0emr5672211e0c.9.1774904956234; Mon, 30 Mar 2026 14:09:16 -0700 (PDT) Received: from ?IPV6:2001:871:22a:d2a7::cebd? ([2001:871:22a:d2a7::cebd]) by smtp.gmail.com with ESMTPSA id 71dfb90a1353d-56d58a333c9sm9989448e0c.13.2026.03.30.14.09.08 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 30 Mar 2026 14:09:15 -0700 (PDT) Message-ID: Date: Mon, 30 Mar 2026 23:09:06 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 0/3] Inline helpers into Rust without full LTO To: Miguel Ojeda , "Russell King (Oracle)" , Alice Ryhl Cc: Ard Biesheuvel , Jamie Cunliffe , Will Deacon , Catalin Marinas , Miguel Ojeda , a.hindborg@kernel.org, acourbot@nvidia.com, akpm@linux-foundation.org, anton.ivanov@cambridgegreys.com, bjorn3_gh@protonmail.com, boqun.feng@gmail.com, dakr@kernel.org, david@davidgow.net, gary@garyguo.net, johannes@sipsolutions.net, justinstitt@google.com, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-um@lists.infradead.org, llvm@lists.linux.dev, lossin@kernel.org, mark.rutland@arm.com, mmaurer@google.com, morbo@google.com, nathan@kernel.org, nick.desaulniers+lkml@gmail.com, nicolas.schier@linux.dev, nsc@kernel.org, peterz@infradead.org, richard@nod.at, rust-for-linux@vger.kernel.org, tmgross@umich.edu, urezki@gmail.com References: <20260322192159.88138-1-ojeda@kernel.org> <20260323000327.111235-1-ojeda@kernel.org> <9cf5a94c-0f37-446c-b63d-ddac5674d220@gmail.com> Content-Language: en-US, de-DE From: Christian Schrefl In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260330_140917_897918_18E0100A X-CRM114-Status: GOOD ( 15.23 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 3/26/26 6:30 PM, Miguel Ojeda wrote: > On Thu, Mar 26, 2026 at 4:18 PM Russell King (Oracle) > wrote: >> >> I'm not sure if this is still true, but I believe it used to be the case >> that the -linux-gnueabi target has one behaviour for enums (fixed size) >> whereas -none-eabi, the size of the type depends on the range of values >> included in the enum. >> >> Certianly, when Arm Ltd were proposing EABI, EABI had the latter >> behaviour, and I think there were cases where Linux used "enum" in >> its UAPI. > > Short enums? I see `c-enum-min-bits` in the armv7a-none-eabi built-in > `rustc` target, and indeed: > > #![no_std] > > #[repr(C)] > enum T { > A, > B, > } > > pub static S: usize = core::mem::size_of::(); > > is 1 for that one, and 4 for the other. I guess we could use a custom target spec, but I'm not sure if that is worth the hassle of adding another one. Cheers, Christian