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=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL 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 7E8B8C433B4 for ; Tue, 27 Apr 2021 21:15:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 54CF6613CE for ; Tue, 27 Apr 2021 21:15:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237055AbhD0VQb (ORCPT ); Tue, 27 Apr 2021 17:16:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236965AbhD0VQa (ORCPT ); Tue, 27 Apr 2021 17:16:30 -0400 Received: from mail-ed1-x52c.google.com (mail-ed1-x52c.google.com [IPv6:2a00:1450:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CBF8FC061574 for ; Tue, 27 Apr 2021 14:15:46 -0700 (PDT) Received: by mail-ed1-x52c.google.com with SMTP id i3so45964162edt.1 for ; Tue, 27 Apr 2021 14:15:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=KjKAsb4G8TL0ol4SRQit/BMD/Sr8mtKntpyCFUbKr94=; b=HMZ+pxK0o6EdaBnD+V+E9N/Mawmh+v/mbYODS7DVQcPiNqU4SkxU35nImij+ex55F8 QcOsMUrumgUV581ugOiAptctCihm0S7ATq5R/Vila2Ytv5piXIcnp5m4Za+dwRXCrg/N KJ9J7Zwqg+dUDikbK5dXV9iVSJME5OJJJIgtR35Kz6Uw+n+ZPjdAIZYdRBTR+E3joPjN L9ejgMaoAEknf6+r51EZve93cKAb2SK38ox7KiAlpXg/ETJIBAqKw1Ym28BqCMRILngn +6AVzzG5Q9fQIGQBW/4cv/NbT2ZhYGAw/i87BSuXogYQAWV5Pya56rbgA/y8/piiuupq Q5/w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=KjKAsb4G8TL0ol4SRQit/BMD/Sr8mtKntpyCFUbKr94=; b=hWP8sMOzVgaqhXCU/HnYvJR2PiPtwC3FvLFdGsFvvrklgsOEoLRW8AFzdhWCZqGe4u LaIrNcZb/584kK45vEI0bdyh1L+28gl63Rb0YIqqSezT8yYsw+B/RpgfYJzSBlUV/dma 4jzCsiWfu3kAQH0h6uhXe6ScvDuKEed2lE6dljlah3XkdldDRAsfepuVpe6kWxWgeQuv GNXXRPvseOA93JMTf5hnUohp3RmYGGzkIkFh/94XOvmsl7NaKsc8u/mU7OgTPbn3vg7a YIPi9sQXUbjBxX1kuFEKR8BpEqmfnm7N0XQLkJESZGgQ7+lwC4k5VBhwTsOU3kP8DDki HGiw== X-Gm-Message-State: AOAM533oDByGAiF2mq0xcOFDh2VImNYR5jThso3yvY899qLchmWvY/7N gIUhMGV9UDbCoIlSEwJKS6VYOLHbwPsIsVm5Gc4b5I8IKbC1 X-Google-Smtp-Source: ABdhPJwwQsrz//4XD2vnKLu5roFhRqir4u8BZB4HhDQJTUYzabBHV0Zmq7bHGPnYJhGST19HKLCcNOSrfBCVjHueL4E= X-Received: by 2002:aa7:c7da:: with SMTP id o26mr6804672eds.244.1619558145094; Tue, 27 Apr 2021 14:15:45 -0700 (PDT) MIME-Version: 1.0 References: <20210309045250.3333311-1-morbo@google.com> In-Reply-To: <20210309045250.3333311-1-morbo@google.com> From: Bill Wendling Date: Tue, 27 Apr 2021 14:15:34 -0700 Message-ID: Subject: Re: [kvm-unit-tests PATCH] Makefile: do not use "libgcc" for clang To: kvm list , Paolo Bonzini Cc: Jim Mattson Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Ping. On Mon, Mar 8, 2021 at 8:53 PM Bill Wendling wrote: > > The -nostdlib flag disables the driver from adding libclang_rt.*.a > during linking. Adding a specific library to the command line then > causes the linker to report unresolved symbols, because the libraries > that resolve those symbols aren't automatically added. Turns out clang > doesn't need to specify that library. > > Signed-off-by: Bill Wendling > --- > Makefile | 6 ++++++ > arm/Makefile.common | 2 ++ > x86/Makefile.common | 2 ++ > 3 files changed, 10 insertions(+) > > diff --git a/Makefile b/Makefile > index e0828fe..61a1276 100644 > --- a/Makefile > +++ b/Makefile > @@ -22,10 +22,16 @@ DESTDIR := $(PREFIX)/share/kvm-unit-tests/ > cc-option = $(shell if $(CC) -Werror $(1) -S -o /dev/null -xc /dev/null \ > > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;) > > +# cc-name > +# Expands to either gcc or clang > +cc-name = $(shell $(CC) -v 2>&1 | grep -q "clang version" && echo clang || echo gcc) > + > #make sure env CFLAGS variable is not used > CFLAGS = > > +ifneq ($(cc-name),clang) > libgcc := $(shell $(CC) --print-libgcc-file-name) > +endif > > libcflat := lib/libcflat.a > cflatobjs := \ > diff --git a/arm/Makefile.common b/arm/Makefile.common > index a123e85..94922aa 100644 > --- a/arm/Makefile.common > +++ b/arm/Makefile.common > @@ -58,7 +58,9 @@ OBJDIRS += lib/arm > libeabi = lib/arm/libeabi.a > eabiobjs = lib/arm/eabi_compat.o > > +ifneq ($(cc-name),clang) > libgcc := $(shell $(CC) $(machine) --print-libgcc-file-name) > +endif > > FLATLIBS = $(libcflat) $(LIBFDT_archive) $(libgcc) $(libeabi) > %.elf: LDFLAGS = -nostdlib $(arch_LDFLAGS) > diff --git a/x86/Makefile.common b/x86/Makefile.common > index 55f7f28..a96b236 100644 > --- a/x86/Makefile.common > +++ b/x86/Makefile.common > @@ -37,7 +37,9 @@ COMMON_CFLAGS += -O1 > # stack.o relies on frame pointers. > KEEP_FRAME_POINTER := y > > +ifneq ($(cc-name),clang) > libgcc := $(shell $(CC) -m$(bits) --print-libgcc-file-name) > +endif > > # We want to keep intermediate file: %.elf and %.o > .PRECIOUS: %.elf %.o > -- > 2.30.1.766.gb4fecdf3b7-goog >