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 C6FFEC433F5 for ; Fri, 7 Jan 2022 14:33:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=yay/1UWPnx6wEwBevcFTcmP9yde2ZJvroDlqY8QkvoQ=; b=pBeMIbt/ndYeqU p3GSiNz7eKWlvN85ubeH8OaGw+QavhUJChISB2YG0y8okl4yIbgGcSK0IsdJDzpMTiYg4mNzEk2kl VA1T7okMd372f55IoGmTJYnhi0UVrcG3WMnrUTFvcqw4gvkzZ77/D8HtJ7XZrnMmVGN35BmCCb6vB s3NAFX4TqRcVIvcszxiFEf7JZgLV1Hzei0wkCznCWoAz3fOTL8Omrkxdw142K48z/dXI4PWhTarOM OzbGExpi2hIiWfLEA3bdRYtL1USIMxh/1pEZUGmi0Rwi8XJb/l6ZjvyHPG4a6rjQ8/0GKiSy8otK5 Ymio8LaNm3njh6JxtirA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n5qHK-004C2G-Jj; Fri, 07 Jan 2022 14:31:38 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n5qHG-004C1U-Ht for linux-arm-kernel@lists.infradead.org; Fri, 07 Jan 2022 14:31:36 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6A5B613A1; Fri, 7 Jan 2022 06:31:31 -0800 (PST) Received: from donnerap.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C96B63F774; Fri, 7 Jan 2022 06:31:30 -0800 (PST) Date: Fri, 7 Jan 2022 14:31:28 +0000 From: Andre Przywara To: Mark Rutland Cc: linux-arm-kernel@lists.infradead.org, Jaxson Han Subject: Re: [boot-wrapper PATCH v2 2/9] Add standard headers Message-ID: <20220107143128.53eb87b2@donnerap.cambridge.arm.com> In-Reply-To: References: <20211222181607.1203191-1-andre.przywara@arm.com> <20211222181607.1203191-3-andre.przywara@arm.com> Organization: ARM X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; aarch64-unknown-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220107_063134_753672_0292968C X-CRM114-Status: GOOD ( 30.96 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 7 Jan 2022 13:49:43 +0000 Mark Rutland wrote: > On Wed, Dec 22, 2021 at 06:16:00PM +0000, Andre Przywara wrote: > > So far we were relying on some standard C headers to be provided by the > > toolchain. This applies for instance to stddef.h and stdint.h. > > As a "bare-metal" application, we should not rely on external headers, > > or even on a toolchain providing them in the first place. > > > > Define our own version of stddef.h and stdint.h, containing just the > > types that we actually need. > > Even a freestanding compiler implementation is required to provide these > headers, and using the compiler versions would avoid unexpected mismatches > (e.g. for builtins). So I don't think the justification as written makes sense. > > Is this because the next patch removes the stdinc paths, and so we don't get > the compiler's implementation of these headers? Yes, exactly. I don't like repeating those either, and understand that even a minimal compiler carries these headers, *somewhere*, but I couldn't find an easy way of including them without being compiler/build specific. I can try harder, and would be happy if someone points out the real solution to this. For the sake of solving this problem I figured that those particular definitions are actually somewhat generic (for all practical purposes), so it was the least involved solution to the real problem, which is to ditch the *other* compiler headers and libraries, as done in patch 3/9. Cheers, Andre > > > > Signed-off-by: Andre Przywara > > --- > > arch/aarch32/include/stdint.h | 19 +++++++++++++++++++ > > arch/aarch64/include/stdint.h | 19 +++++++++++++++++++ > > include/stddef.h | 15 +++++++++++++++ > > 3 files changed, 53 insertions(+) > > create mode 100644 arch/aarch32/include/stdint.h > > create mode 100644 arch/aarch64/include/stdint.h > > create mode 100644 include/stddef.h > > > > diff --git a/arch/aarch32/include/stdint.h b/arch/aarch32/include/stdint.h > > new file mode 100644 > > index 0000000..77546f0 > > --- /dev/null > > +++ b/arch/aarch32/include/stdint.h > > @@ -0,0 +1,19 @@ > > +/* > > + * arch/aarch32/include/stdint.h > > + * > > + * Copyright (C) 2021 ARM Limited. All rights reserved. > > + * > > + * Use of this source code is governed by a BSD-style license that can be > > + * found in the LICENSE.txt file. > > + */ > > +#ifndef STDINT_H__ > > +#define STDINT_H__ > > + > > +typedef unsigned char uint8_t; > > +typedef unsigned short int uint16_t; > > +typedef unsigned int uint32_t; > > +typedef unsigned long long int uint64_t; > > + > > +typedef unsigned int uintptr_t; > > + > > +#endif > > diff --git a/arch/aarch64/include/stdint.h b/arch/aarch64/include/stdint.h > > new file mode 100644 > > index 0000000..92c2603 > > --- /dev/null > > +++ b/arch/aarch64/include/stdint.h > > @@ -0,0 +1,19 @@ > > +/* > > + * arch/aarch64/include/stdint.h > > + * > > + * Copyright (C) 2021 ARM Limited. All rights reserved. > > + * > > + * Use of this source code is governed by a BSD-style license that can be > > + * found in the LICENSE.txt file. > > + */ > > +#ifndef STDINT_H__ > > +#define STDINT_H__ > > + > > +typedef unsigned char uint8_t; > > +typedef unsigned short int uint16_t; > > +typedef unsigned int uint32_t; > > +typedef unsigned long int uint64_t; > > + > > +typedef unsigned long int uintptr_t; > > + > > +#endif > > diff --git a/include/stddef.h b/include/stddef.h > > new file mode 100644 > > index 0000000..3208b10 > > --- /dev/null > > +++ b/include/stddef.h > > @@ -0,0 +1,15 @@ > > +/* > > + * include/stddef.h - standard data type definitions > > + * > > + * Copyright (C) 2021 ARM Limited. All rights reserved. > > + * > > + * Use of this source code is governed by a BSD-style license that can be > > + * found in the LICENSE.txt file. > > + */ > > +#ifndef STDDEF_H__ > > +#define STDDEF_H__ > > + > > +typedef unsigned long int size_t; > > +typedef signed long int ssize_t; > > + > > +#endif > > -- > > 2.25.1 > > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel