From owner-freebsd-ppc@freebsd.org Tue Nov 29 22:57:08 2016 Return-Path: Delivered-To: freebsd-ppc@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 993E2C5CB65; Tue, 29 Nov 2016 22:57:08 +0000 (UTC) (envelope-from carpeddiem@gmail.com) Received: from mail-qt0-x243.google.com (mail-qt0-x243.google.com [IPv6:2607:f8b0:400d:c0d::243]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4D71C1F90; Tue, 29 Nov 2016 22:57:08 +0000 (UTC) (envelope-from carpeddiem@gmail.com) Received: by mail-qt0-x243.google.com with SMTP id n34so17515662qtb.3; Tue, 29 Nov 2016 14:57:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=fjQmshotrYKNYXTZ80MXDPbKXCsouRk4OyJGmJyj4Sk=; b=Bqqi4BQbTycFm2UoC8Evd/ayF6ivK4/Btej/RmYkGdBZfUw2cQ+nZqYagEokB2MG6b MqCdYKQuz3J+NImRd/GGnt8kx4Yr6Vpthk7k9EIfQwgUADDMnSMo4ylWQyqiPA/PJCT+ QAMqpy0ru+5KoT5l0mt2+ODzQ8pLDbVgeTOPZYV16XxFn4ajVJeOyY0pNJdFJHgrsx4h y151z6mt2hK6ypD7gUT71yTDfN5jj6L/xmu0lmTfFyLH1PcFi+kQO0yvwBjzFBETSZv7 3UTWKaeda9v36QeFcRHIZS+HUg8a0mAlRD8/V6gqrl7b4Nw8KmZq8PyYF89aC7tVyIHv 57BQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=fjQmshotrYKNYXTZ80MXDPbKXCsouRk4OyJGmJyj4Sk=; b=FN6OenOEmZgHfFZoYuWh/OcE3bTPwna5LOdP6d6q2VuSSaBRjrLYLJimNOHkkS+YYy vEnThTkckZlI2XPt8md5B1jp0KS1yRii5REh2EvKbQRf7Qr+yUqKVSVcm32j7RqCIbJo npySKXhjhcuTw+DgEnHOs1iHXVDXF0L5Fv8lRurQW540SWjGbjjw90fgCQJSHVfq2pZW 0sVpjG61L7FFEKjY3DPcGs4oGhq5OHZAv2dvq5qfpfHBuBAjQw3q/bmUOoT19bhJjSOP BDMQzaaw2Vi2vn0yBshNr1sN4NOjH6xt7OQ98vz5KU19L8okDgsdnreh67qk4L3QSgEI 7clg== X-Gm-Message-State: AKaTC03pxJERdL9r2yfKrh4SSC+kNpHkNoDW94Zldhe241nROn3bFQOWGZveRlpEl1YZs310dcEv1KUZsFfVRA== X-Received: by 10.200.53.239 with SMTP id l44mr29330247qtb.60.1480460227355; Tue, 29 Nov 2016 14:57:07 -0800 (PST) MIME-Version: 1.0 Sender: carpeddiem@gmail.com Received: by 10.12.132.163 with HTTP; Tue, 29 Nov 2016 14:56:46 -0800 (PST) In-Reply-To: <750FCE4D-F25B-46E1-9383-B8A94AAA8792@dsl-only.net> References: <750FCE4D-F25B-46E1-9383-B8A94AAA8792@dsl-only.net> From: Ed Maste Date: Tue, 29 Nov 2016 17:56:46 -0500 X-Google-Sender-Auth: tFQfJ-UAOCv2tw0Y9uLxQnXoPeo Message-ID: Subject: Re: WITH_LLVM_LIBUNWIND vs. WITHOUT_LLVM_LIBUNWIND, clang vs. gcc (such as devel/powerpc64-xtoolchain-gcc ): What is intended to be required for C++ exceptions to work? To: Mark Millard Cc: FreeBSD Toolchain , FreeBSD PowerPC ML , Dimitry Andric Content-Type: text/plain; charset=UTF-8 X-BeenThere: freebsd-ppc@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Porting FreeBSD to the PowerPC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 29 Nov 2016 22:57:08 -0000 On 29 November 2016 at 16:46, Mark Millard wrote: > > > Summary: Does using clang 3.9.0 as the system compiler imply one should or > must (eventually?) use WITH_LLVM_LIBUNWIND to have C++ exceptions work? > > Do WITH_LLVM_LIBUNWIND and WITHOUT_LLVM_LIBUNWIND have the same criteria > for what dwarfdump should show for the exception information (if the > information to be shown is to be correct/sufficient for libunwind)? It does not. It should be possible to build a functional system both WITH_ and WITHOUT_LLVM_LIBUNWIND. The compiler is unaware of the _LLVM_LIBUNWIND setting. Both unwind libraries use the same unwind data. Eventually new features may show up in Clang and LLVM's libunwind (and new versions of GNU's unwinder) that won't work with the old unwinder. > Your answer's detail might indicate that I've misdirected the llvm folks > in submittals like https://llvm.org/bugs/show_bug.cgi?id=26844 . > > There is also the question of if/when llvm's libunwind is ready to be used > for powerpc64 or powerpc (or . . .) if there are architecture specifics > involved. That answer might determine when C++ exceptions work (and so > when devel/kyua might have a chance to work) and is sort of separate from > the main question here but is still of interest overall. > > Should powerpc64 and powerpc clang 3.9.0 testing be using > WITH_LLVM_LIBUNWIND ? WITHOUT_LLVM_LIBUNWIND ? Both? For testing I think WITH_LLVM_LIBUNWIND is the interesting case. My eventual goal is to have a functioning Clang, LLD, LLDB, libunwind, and ELF Tool Chain on all of our supported architectures.