You'd think, but no - there's no guarantee that the shipped binary packages can be built with the shipped toolchain or shipped dependencies.

> If you are building a new Linux distribution based on Ubuntu, I don't even understand why you would want to reuse binaries they built.

Because it's entirely unnecessary? Building the entire archive is a huge amount of effort.

> This post would be more meaningful if it literally quoted from unfavorable license terms used by Ubuntu to actually prevent people from making derivatives. Saying that Canonical "appears to require" something is using weasel words.

The terms are at http://www.ubuntu.com/legal/terms-and-policies/intellectual-... - I probably should have linked them, I've just been writing about this enough lately that it's easy to forget that people might read a single post without context.

That problem will be with us as long as we use binaries as the primary means of distribution. If you consider that to be a problem, you could put effort into distributions where the packaging is the source code. I know I do.

> Because it's entirely unnecessary? Building the entire archive is a huge amount of effort.

How do you know that the source code provided actually corresponds to the binaries unless you compile them yourself[ with a toolchain you compiled yourself [...]]?

> The terms are at http://www.ubuntu.com/legal/terms-and-policies/intellectual-.... - I probably should have linked them, I've just been writing about this enough lately that it's easy to forget that people might read a single post without context.

No company's policies are perfect. You might be more effective trying to deal with the overall distribution of how software is done rather than imperfections in community leaders. There is a point of diminishing returns in focusing on a small subset of the companies out there while completely ignoring the rest.

I do consider it to be a problem, but since reality is problematic I think policies that force people to rebuild all binaries before they can redistribute them are harmful.

> How do you know that the source code provided actually corresponds to the binaries unless you compile them yourself[ with a toolchain you compiled yourself [...]]?

I don't, but I also don't have a verifiable path to bootstrapping a toolchain. I trust that Canonical haven't backdoored their packages.

> You might be more effective trying to deal with the overall distribution of how software is done rather than imperfections in community leaders.

I'm interested in it being straightforward for people to produce modified derivatives of the market leader, ie Ubuntu. I can achieve that in two ways:

1) Helping convince Canonical to change their IP policy 2) Helping convince Canonical to rearchitect their entire distribution infrastructure

(1) strikes me as being easier, so that's what I've chosen to work on.

You don't have a moral right to base a distribution on binaries produced by some other distribution. Unless you are going to produce actual evidence of a legal violation you really don't have anything here.

You do not need a verifiable path to bootstrapping a toolchain to reduce surface area of attack to just the toolchain.

That being said, you could try building Clang with GCC and then GCC with Clang (or vice versa) to break any exploits designed to persist in either one indefinitely unless you are the victim of a really special hypothetical attack that targets both simultaneously, although I imagine you could interleave multiple GCC and Clang versions to make such an attack even harder to pull off or even add more compilers to the mix like EKOPath. That should reduce the attack surface area to binutils.

I am typing this on a system running Gentoo that has only 3 proprietary packages installed, with one being Intel's microcode. In time, I hope to lower that number to zero. If you are concerned about this and do not run a source-based distribution, I suggest that you switch.

Anyway, I am happy to see that building from source is becoming easier for users of Debian and presumably Ubuntu by extension.

If the shipped source doesn't contain enough information to actually perform a build surely that's a straight-up GPL violation (and a far more serious one than any possible ZFS issue, and one that you're in a position to do something about as a copyright holder). If the shipped source doesn't include whatever their developers actually use to build (and I refuse to believe an organization like Ubuntu wouldn't have a unified "build it all" script, or at least a README that described the steps you needed to take) then how can it possibly be the preferred form for making modifications?

Package A's source code contains some undefined behaviour that gcc 4.4 tolerates. The distribution upgrades to gcc 5.1 and the build now breaks, but nobody notices because no new version of Package A has been uploaded and so no new build has been performed. Is your position that it was in compliance with the GPL before the gcc transition, and in violation afterwards?

They don't.

I mean a developer working at Canonical, trying to make a change to one of the packages they're preparing for distribution, has to have some way to answer the question "what version of gcc is being used to build this package". Whether that information is kept in the source tree, on their wiki, or on a post-it on the employee fridge - in any case, it's part of the source in the preferred form for making modifications, because it's, well, part of what the employees use to make modifications.

The distribution isn't rebuilt every cycle. If no new source release has been uploaded, the existing binary will be used for the next release.

I think that Matthew might be suggesting that not all packages are rebuilt with every release? A binary package might be compiled with GCC-4, then the distribution is upgraded to GCC-5, dropping GCC-4. If for some reason the package is not compatible with the new compiler, you would then be in a situation where the binary cannot be recreated from source without outside tools. Do you know if Canonical recompiles everything on each update to the toolchain?

Why would it be? Build and testing systems for something like a Linux distribution are far more complex systems than a simple script. In any case, there's no requirement in the GPL (or any other OSI-approved license AFAIK) to include components outside of the software itself to simplify building and installing. Of course, there are a variety of things like package managers that do simplify the process but there's no requirement in the GPL that it be straightforward to install from sources.