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 X-Spam-Level: X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E7951C433B4 for ; Tue, 13 Apr 2021 20:36:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BFB6F60FE5 for ; Tue, 13 Apr 2021 20:36:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230213AbhDMUgm (ORCPT ); Tue, 13 Apr 2021 16:36:42 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:34322 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229914AbhDMUgm (ORCPT ); Tue, 13 Apr 2021 16:36:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1618346181; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=WTY3hhv4d7/Xxm5AZyz+178fLEqQaYg9wqasB6pga1c=; b=RU81+piAguUXb59dGJ8CLxyVknevEEj4CS9HRuNH4P4wdOyE5HMUlNm/fJREpyE5NfNVtg 09PPyEalBg0DT8yqo1axHgemWNt2fIG2Jg4rzyMH0SBXW6gNsZXES83b0USL1wMFN9gn5+ dSwlgqmtf7eKM0jkbwglFaOKdwERPQU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-343-ZqxKfaZ9MQqIICUGbshbUg-1; Tue, 13 Apr 2021 16:36:17 -0400 X-MC-Unique: ZqxKfaZ9MQqIICUGbshbUg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A04498E6E6F; Tue, 13 Apr 2021 20:35:52 +0000 (UTC) Received: from krava (unknown [10.40.192.129]) by smtp.corp.redhat.com (Postfix) with SMTP id CC8631084392; Tue, 13 Apr 2021 20:35:50 +0000 (UTC) Date: Tue, 13 Apr 2021 22:35:49 +0200 From: Jiri Olsa To: Nick Desaulniers Cc: Jiri Olsa , bpf , Andrii Nakryiko , Arnaldo Carvalho de Melo , kernel-team@fb.com, Sedat Dilek , Yonghong Song Subject: Re: [PATCH bpf-next v2 0/5] bpf: tools: support build selftests/bpf with clang Message-ID: References: <20210412142905.266942-1-yhs@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Tue, Apr 13, 2021 at 11:56:33AM -0700, Nick Desaulniers wrote: > On Tue, Apr 13, 2021 at 11:46 AM Nick Desaulniers > wrote: > > > > On Mon, Apr 12, 2021 at 5:31 PM Yonghong Song wrote: > > > > > > > > > > > > On 4/12/21 5:02 PM, Nick Desaulniers wrote: > > > > On Mon, Apr 12, 2021 at 4:58 PM Nick Desaulniers > > > > wrote: > > > >> > > > >> On Mon, Apr 12, 2021 at 7:29 AM Yonghong Song wrote: > > > >>> > > > >>> To build kernel with clang, people typically use > > > >>> make -j60 LLVM=1 LLVM_IAS=1 > > > >>> LLVM_IAS=1 is not required for non-LTO build but > > > >>> is required for LTO build. In my environment, > > > >>> I am always having LLVM_IAS=1 regardless of > > > >>> whether LTO is enabled or not. > > > >>> > > > >>> After kernel is build with clang, the following command > > > >>> can be used to build selftests with clang: > > > >>> make -j60 -C tools/testing/selftests/bpf LLVM=1 LLVM_IAS=1 > > > >> > > > >> Thank you for the series Yonghong. When I test the above command with > > > >> your series applied, I observe: > > > >> tools/include/tools/libc_compat.h:11:21: error: static declaration of > > > >> 'reallocarray' follows non-static declaration > > > >> static inline void *reallocarray(void *ptr, size_t nmemb, size_t size) > > > >> ^ > > > >> /usr/include/stdlib.h:559:14: note: previous declaration is here > > > >> extern void *reallocarray (void *__ptr, size_t __nmemb, size_t __size) > > > >> ^ > > > >> so perhaps the detection of > > > >> COMPAT_NEED_REALLOCARRAY/feature-reallocarray is incorrect? > > > > > > > > Is this related to _DEFAULT_SOURCE vs _GNU_SOURCE. via man 3 reallocarray: > > > > reallocarray(): > > > > Since glibc 2.29: > > > > _DEFAULT_SOURCE > > > > Glibc 2.28 and earlier: > > > > _GNU_SOURCE > > > > > > > > > > You can try the following patch to see whether it works or not. > > > > > > diff --git a/tools/build/feature/test-reallocarray.c > > > b/tools/build/feature/test-reallocarray.c > > > index 8f6743e31da7..500cdeca07a7 100644 > > > --- a/tools/build/feature/test-reallocarray.c > > > +++ b/tools/build/feature/test-reallocarray.c > > > @@ -1,5 +1,5 @@ > > > // SPDX-License-Identifier: GPL-2.0 > > > -#define _GNU_SOURCE > > > +#define _DEFAULT_SOURCE > > > #include > > > > > > int main(void) > > > @@ -7,4 +7,4 @@ int main(void) > > > return !!reallocarray(NULL, 1, 1); > > > } > > > > > > -#undef _GNU_SOURCE > > > +#undef _DEFAULT_SOURCE > > > > Yeah, I had tried that. No luck though; same error message. Even: > > > > $ cat foo.c > > #define _DEFAULT_SOURCE > > #include > > void *reallocarray(void *ptr, size_t nmemb, size_t size) { return (void*)0; }; > > $ clang -c foo.c > > $ echo $? > > 0 > > > > So I'm not sure precisely what's going on here. I probably have to go > > digging around to understand tools/build/feature/ anyways. With your > > v3 applied, I consistently see: > > No zlib found > > and yet, I certainly do have zlib on my host. > > https://stackoverflow.com/a/54558861 > > Jiri, any tips on how to debug feature detection in > tools/build/feature/Makefile? for quick check, there's output file for each test, like: [jolsa@krava feature]$ ls -l *.make.output -rw-rw-r--. 1 jolsa jolsa 0 Apr 8 20:25 test-all.make.output -rw-rw-r--. 1 jolsa jolsa 182 Apr 9 15:52 test-bionic.make.output -rw-rw-r--. 1 jolsa jolsa 0 Apr 8 20:25 test-cplus-demangle.make.output -rw-rw-r--. 1 jolsa jolsa 145 Apr 9 15:52 test-jvmti.make.output -rw-rw-r--. 1 jolsa jolsa 0 Apr 8 20:25 test-libbabeltrace.make.output -rw-rw-r--. 1 jolsa jolsa 0 Apr 8 20:25 test-libbpf.make.output -rw-rw-r--. 1 jolsa jolsa 0 Apr 8 20:25 test-libdebuginfod.make.output -rw-rw-r--. 1 jolsa jolsa 193 Apr 9 15:52 test-libunwind-aarch64.make.output -rw-rw-r--. 1 jolsa jolsa 177 Apr 9 15:52 test-libunwind-x86.make.output [jolsa@krava feature]$ cat test-libunwind-aarch64.make.output test-libunwind-aarch64.c:2:10: fatal error: libunwind-aarch64.h: No such file or directory 2 | #include | ^~~~~~~~~~~~~~~~~~~~~ compilation terminated. [jolsa@krava feature]$ cat test-libunwind-x86.make.output test-libunwind-x86.c:2:10: fatal error: libunwind-x86.h: No such file or directory 2 | #include | ^~~~~~~~~~~~~~~~~ zlib should be done by: [jolsa@krava feature]$ make test-zlib.bin gcc -MD -Wall -Werror -o test-zlib.bin test-zlib.c > test-zlib.make.output 2>&1 -lz I can try to recreate, how do you build? jirka