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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D39E2C46CA3 for ; Sun, 3 Dec 2023 09:50:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233360AbjLCJt4 (ORCPT ); Sun, 3 Dec 2023 04:49:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233328AbjLCJty (ORCPT ); Sun, 3 Dec 2023 04:49:54 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B2BC3DA for ; Sun, 3 Dec 2023 01:50:00 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 099D3C433CB; Sun, 3 Dec 2023 09:49:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701597000; bh=3fREL+3pDb0+f3gpXJDWy/Z+fjSVV4sYVi1Ga8WtaHw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VNv2/I0y1QaQgNoItB2fCs1RK2AgJtD5NdVHjX92RWhrLjqitS+cRVeZ2kXIsGx8o QER7zjLtrPvCDVpDGyc3FQjR1VGYW3GSPNVdnBPNTd/weX/xjWmn3qQ+K1pop+vvcg GFEsnbwuHQbnxVpzlV+Nq196TtY3G02V8Ierf2Za1v9CKfTZdcZyFKZPK5izOAbYYl ZOpkXYUBx5i1XQIVUb6TT7YK1VqGX0xTOhvmbj9cb/vYAtzzh/DiO1FD7tn+eXX70Q AtM5DljHuHWcL9uKAyXzFm49NNpivgg0zf9/3DC1s2cXsmpzfMak3IwicdamK9Zc7m G3A13S5DzjkPg== From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: Masahiro Yamada , Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Tom Rix , linux-kernel@vger.kernel.org, llvm@lists.linux.dev Subject: [PATCH v2 4/4] modpost: remove unreachable code after fatal() Date: Sun, 3 Dec 2023 18:49:34 +0900 Message-Id: <20231203094934.1908270-4-masahiroy@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20231203094934.1908270-1-masahiroy@kernel.org> References: <20231203094934.1908270-1-masahiroy@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now compilers can recognize fatal() never returns. While GCC 4.5 dropped support for -Wunreachable-code, Clang is capable of detecting the unreachable code. $ make HOSTCC=clang HOSTCFLAGS=-Wunreachable-code-return [snip] HOSTCC scripts/mod/modpost.o scripts/mod/modpost.c:520:11: warning: 'return' will never be executed [-Wunreachable-code-return] return 0; ^ scripts/mod/modpost.c:477:10: warning: 'return' will never be executed [-Wunreachable-code-return] return 0; ^ 2 warnings generated. Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor --- Changes in v2: - Change the patch order - Update the commit description and add warning example. scripts/mod/modpost.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 3233946fa5f6..e2bc180cecc8 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -476,11 +476,9 @@ static int parse_elf(struct elf_info *info, const char *filename) fatal("%s: not relocatable object.", filename); /* Check if file offset is correct */ - if (hdr->e_shoff > info->size) { + if (hdr->e_shoff > info->size) fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\n", (unsigned long)hdr->e_shoff, filename, info->size); - return 0; - } if (hdr->e_shnum == SHN_UNDEF) { /* @@ -518,12 +516,11 @@ static int parse_elf(struct elf_info *info, const char *filename) const char *secname; int nobits = sechdrs[i].sh_type == SHT_NOBITS; - if (!nobits && sechdrs[i].sh_offset > info->size) { + if (!nobits && sechdrs[i].sh_offset > info->size) fatal("%s is truncated. sechdrs[i].sh_offset=%lu > sizeof(*hrd)=%zu\n", filename, (unsigned long)sechdrs[i].sh_offset, sizeof(*hdr)); - return 0; - } + secname = secstrings + sechdrs[i].sh_name; if (strcmp(secname, ".modinfo") == 0) { if (nobits) -- 2.40.1