From owner-freebsd-toolchain@freebsd.org Fri Apr 14 21:35:08 2017 Return-Path: Delivered-To: freebsd-toolchain@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 9E6A8D3C00A for ; Fri, 14 Apr 2017 21:35:08 +0000 (UTC) (envelope-from dimitry@andric.com) Received: from tensor.andric.com (tensor.andric.com [IPv6:2001:470:7a58:1::1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "tensor.andric.com", Issuer "COMODO RSA Domain Validation Secure Server CA" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 6AAAA976 for ; Fri, 14 Apr 2017 21:35:08 +0000 (UTC) (envelope-from dimitry@andric.com) Received: from [IPv6:2001:470:7a58::a52e:a92f:39e6:6900] (unknown [IPv6:2001:470:7a58:0:a52e:a92f:39e6:6900]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by tensor.andric.com (Postfix) with ESMTPSA id B62B62420E; Fri, 14 Apr 2017 23:35:05 +0200 (CEST) From: Dimitry Andric Message-Id: <7DB9F23E-2D55-44C3-AA91-C209BF584C4A@andric.com> Content-Type: multipart/signed; boundary="Apple-Mail=_BE02AFEE-DF60-4B78-A153-AEC3C75C2C9D"; protocol="application/pgp-signature"; micalg=pgp-sha1 Mime-Version: 1.0 (Mac OS X Mail 10.3 \(3273\)) Subject: Re: WITH_LLD_IS_LD vs default WITHOUT_SYSTEM_COMPILER: What are the reasons? Date: Fri, 14 Apr 2017 23:35:00 +0200 In-Reply-To: Cc: FreeBSD Toolchain To: Mark Millard References: X-Mailer: Apple Mail (2.3273) X-BeenThere: freebsd-toolchain@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Maintenance of FreeBSD's integrated toolchain List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Apr 2017 21:35:08 -0000 --Apple-Mail=_BE02AFEE-DF60-4B78-A153-AEC3C75C2C9D Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii On 14 Apr 2017, at 22:40, Mark Millard wrote: > > man src.conf (from -r315914 ) reports: > > WITH_LLD_IS_LD > Set to use LLVM's LLD as the system linker, instead of GNU > binutils ld. > > This is a default setting on arm64/aarch64. When set, these > options are also in effect: > > WITHOUT_SYSTEM_COMPILER (unless WITH_SYSTEM_COMPILER is set > explicitly) > > I'm curious about: > > A) Why there is a bias to avoid the system compiler? These are just the defaults, detected by the script that generates src.conf.5. The setting of MK_SYSTEM_COMPILER is actually dependent on the host, so it's technically incorrect to have src.conf.5 mention that it is off by default. > and by contrast: > > B) What sort of context justifies explicitly setting > WITH_SYSTEM_COMPILER when WITH_LLD_IS_LD is in use? The settings are mostly orthogonal. MK_SYSTEM_COMPILER was created to avoid building a bootstrap compiler, if the system (host) compiler is new enough. At some point you could also image a MK_SYSTEM_LINKER setting, which would avoid building the bootstrap linker, if the system linker is new enough. -Dimitry --Apple-Mail=_BE02AFEE-DF60-4B78-A153-AEC3C75C2C9D Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.30 iEYEARECAAYFAljxQIkACgkQsF6jCi4glqN7jwCgzOzQK+lzSzcmbTPijcqe3qiu GRMAnA9dg08iVxz+kA28nvSaU8cI4Nsd =csZi -----END PGP SIGNATURE----- --Apple-Mail=_BE02AFEE-DF60-4B78-A153-AEC3C75C2C9D--