From nobody Fri Dec 19 04:01:52 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 2CE0CC46467 for ; Tue, 10 Jan 2023 07:30:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238001AbjAJHaA (ORCPT ); Tue, 10 Jan 2023 02:30:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237888AbjAJH33 (ORCPT ); Tue, 10 Jan 2023 02:29:29 -0500 Received: from 1wt.eu (wtarreau.pck.nerim.net [62.212.114.60]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id BCD7053725 for ; Mon, 9 Jan 2023 23:27:03 -0800 (PST) Received: (from willy@localhost) by pcw.home.local (8.15.2/8.15.2/Submit) id 30A7OcV3003939; Tue, 10 Jan 2023 08:24:38 +0100 From: Willy Tarreau To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, Sven Schnelle , Willy Tarreau Subject: [PATCH v2 12/22] tools/nolibc: export environ as a weak symbol on s390 Date: Tue, 10 Jan 2023 08:24:24 +0100 Message-Id: <20230110072434.3863-13-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" From: Sven Schnelle 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 s390 both with environ inherited from _start and extracted from envp. Signed-off-by: Sven Schnelle Signed-off-by: Willy Tarreau --- tools/include/nolibc/arch-s390.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/include/nolibc/arch-s390.h b/tools/include/nolibc/arch-s= 390.h index b58f64d47b82..039b454e79f0 100644 --- a/tools/include/nolibc/arch-s390.h +++ b/tools/include/nolibc/arch-s390.h @@ -159,6 +159,8 @@ struct sys_stat_struct { _arg1; \ }) =20 +char **environ __attribute__((weak)); + /* startup code */ void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) _start(= void) { @@ -174,6 +176,8 @@ void __attribute__((weak,noreturn,optimize("omit-frame-= pointer"))) _start(void) "la %r4,8(%r4)\n" /* advance pointer */ "jnz 0b\n" /* no -> test next pointer */ /* yes -> r4 now contains start of envp */ + "larl %r1,environ\n" + "stg %r4,0(%r1)\n" =20 "aghi %r15,-160\n" /* allocate new stackframe */ "xc 0(8,%r15),0(%r15)\n" /* clear backchain */ --=20 2.17.5