From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Marusich Subject: Re: diverse double compilation: using $ORIGIN? Date: Thu, 09 Nov 2017 20:53:38 -0800 Message-ID: <87bmkaray5.fsf@gmail.com> References: <87wp3agd60.fsf@elephly.net> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:50583) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eD1KE-0000nC-MP for guix-devel@gnu.org; Thu, 09 Nov 2017 23:53:57 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eD1K5-0002lr-9C for guix-devel@gnu.org; Thu, 09 Nov 2017 23:53:48 -0500 Received: from mail-pf0-x235.google.com ([2607:f8b0:400e:c00::235]:49024) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1eD1K5-0002ja-2C for guix-devel@gnu.org; Thu, 09 Nov 2017 23:53:45 -0500 Received: by mail-pf0-x235.google.com with SMTP id b79so5953989pfk.5 for ; Thu, 09 Nov 2017 20:53:42 -0800 (PST) List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Ricardo Wurmus Cc: guix-devel@gnu.org, bootstrappable@freelists.org --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Ricardo Wurmus writes: > Since the GCC build procedure is performed at least two > times (once with the bootstrap compiler, and then again with the GCC > variant this produces), the resulting GCC binaries should be identical. > > Except that they are not. One of the reasons is that the binaries > that Guix produces embed the target output directories. This means > that the two compiler binaries that result from diverse double > compilation will *always* differ in at least the embedded paths, such > as paths to itself (e.g. to binaries in the libexec directory) and > paths to. What ever happened to the intensional model (i.e., a content-addressed store)? If derivation outputs were content-addressed, this would not be a problem, right? Dolstra's thesis presented some ideas for how to rewrite self-references in derivation outputs under the intensional model. I've casually looked into what happened with the intensional model since his thesis was written, but I don't really know why it hasn't been implemented. All I know is that Dolstra and the Nix devs seem to have moved away from that idea; I never really learned the reason(s) why. =2D-=20 Chris --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEy/WXVcvn5+/vGD+x3UCaFdgiRp0FAloFMNIACgkQ3UCaFdgi Rp3rVRAArzCmTEQsPa0Plhi5AuTv841eaP3ttsNZhbDWP81y99SQKzMj5h5TwOl/ OYuXi93dTvDxYxulS1rwPURbc9gP7I3CUxAN++1E0gEEzFMKl+yMmx5KnNR6mFvc pdkqxo9xLwJ/MOCx25dcUL7BhBasUDp0IeAmHIOvCnvBipe18xi2bPv+cEBNP1ww 3hEgj3BU/WyzrNUHpUUSSwdRsNmMDlEELi2ReU3CLQmcPh/mIOSH3d6C73J4OFX9 K85GB3QSfrTIA75vCohyZUu8GjUe7pg/alDPpn/ZSr8+XHZTtVdS5NRCEkNT5NXK aQMLvheFwjJEkHQx3PcP4aF69bVd9z0UBtxMi+lGY1sbG//lU+0uwE6hRK6mZNwI V66Sz59t4m1AE/HsVvleD9DLa70G2Ak+AguUfFSOznRDwVhEqHhkYHdVmi+pyShN 6rjH3E+NIQFr0RelOEdBTqMOyhLTnNH6XzSuuT/kOH7bfu69Q+h81GhMRstun2IO jkY42dCCkp/gyBrvfpiQRFL0/wXMlDQoYu1bdDv5Hz73owT8w94DwcpRHEVNfD/C YQw4aqdNxfQGkwkf/C+42FCaBd8Zhj2KRHduzrU6yBkl6E75tafk7VsCrcq+JHUI MLukyGkCf8+s3lrpuBKgGTd79+xcWGhh0ZbD63lWFScCcxzGFJ0= =mo14 -----END PGP SIGNATURE----- --=-=-=--