From nobody Fri Dec 19 04:02:17 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 8F889C54EBE for ; Tue, 10 Jan 2023 07:29:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237971AbjAJH3x (ORCPT ); Tue, 10 Jan 2023 02:29:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46970 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237835AbjAJH3X (ORCPT ); Tue, 10 Jan 2023 02:29:23 -0500 Received: from 1wt.eu (wtarreau.pck.nerim.net [62.212.114.60]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 193C453711 for ; Mon, 9 Jan 2023 23:27:02 -0800 (PST) Received: (from willy@localhost) by pcw.home.local (8.15.2/8.15.2/Submit) id 30A7OcjL003938; Tue, 10 Jan 2023 08:24:38 +0100 From: Willy Tarreau To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, Willy Tarreau Subject: [PATCH v2 11/22] tools/nolibc: export environ as a weak symbol on riscv Date: Tue, 10 Jan 2023 08:24:23 +0100 Message-Id: <20230110072434.3863-12-w@1wt.eu> X-Mailer: git-send-email 2.17.5 In-Reply-To: <20230110072434.3863-1-w@1wt.eu> References: <20230110072434.3863-1-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