From nobody Fri Dec 19 20:05:32 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 28447C5479D for ; Mon, 9 Jan 2023 08:51:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236782AbjAIIvh (ORCPT ); Mon, 9 Jan 2023 03:51:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236692AbjAIItf (ORCPT ); Mon, 9 Jan 2023 03:49:35 -0500 Received: from 1wt.eu (wtarreau.pck.nerim.net [62.212.114.60]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 1AA1D1742E for ; Mon, 9 Jan 2023 00:44:06 -0800 (PST) Received: (from willy@localhost) by pcw.home.local (8.15.2/8.15.2/Submit) id 3098gDqQ027430; Mon, 9 Jan 2023 09:42:13 +0100 From: Willy Tarreau To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, Willy Tarreau Subject: [PATCH 11/22] tools/nolibc: export environ as a weak symbol on riscv Date: Mon, 9 Jan 2023 09:41:57 +0100 Message-Id: <20230109084208.27355-12-w@1wt.eu> X-Mailer: git-send-email 2.17.5 In-Reply-To: <20230109084208.27355-1-w@1wt.eu> References: <20230109084208.27355-1-w@1wt.eu> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The environ is retrieved from the _start code and is easy to store at this moment. Let's declare the variable weak and store the value into it. By not being static it will be visible to all units. By being weak, if some programs already declared it, they will continue to be able to use it. This was tested on riscv64 both with environ inherited from _start and extracted from envp. Signed-off-by: Willy Tarreau --- tools/include/nolibc/arch-riscv.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-= riscv.h index c2b5db383d96..1608e6bd94b9 100644 --- a/tools/include/nolibc/arch-riscv.h +++ b/tools/include/nolibc/arch-riscv.h @@ -170,6 +170,8 @@ struct sys_stat_struct { _arg1; \ }) =20 +char **environ __attribute__((weak)); + /* startup code */ void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(= void) { @@ -183,6 +185,8 @@ void __attribute__((weak,noreturn,optimize("omit-frame-= pointer"))) _start(void) "slli a2, a0, "PTRLOG"\n" // envp (a2) =3D SZREG*argc ... "add a2, a2, "SZREG"\n" // + SZREG (skip null) "add a2,a2,a1\n" // + argv + "lui a3, %hi(environ)\n" // a3 =3D &environ (high bits) + "sd a2,%lo(environ)(a3)\n" // store envp(a2) into environ "andi sp,a1,-16\n" // sp must be 16-byte aligned "call main\n" // main() returns the status code, we'll ex= it with it. "li a7, 93\n" // NR_exit =3D=3D 93 --=20 2.17.5