Sylvestre's blog

A week after the Euro LLVM conference, I am glad to share the results I presented and discussed during the event.

1) Parallel building infrastructure using clang instead of gcc

Based on the work that Alexander Pashaliyski and I did during the GSoC 2012, we are now able to automatically rebuild each package uploaded in Unstable transparently. Results are published here:
http://buildd-clang.debian.net/
This provides a quick and easy way to any Debian contributors or upstream packaged in Debian to check how the package behaves with clang.
For Debian Developer and maintainer, a per maintainer view is also provided. This will list all packages maintained by a Debian packager. My page as example

Here is an example of the list of package:

And an example of package failing:

At time of writing, most of the packages in unstable have been rebuilt (16 % are remaining). However, due to resource constraints, only amd64 packages are built. Contact me if you have resources to share for other architectures.

Thanks to Paul Wise, the PTS (Debian package tracking system) proposes a link to the clang build logs (failing or not).

A repository will be automatically updated with the results of these builds (once I find the time to get into buildd).

2) clang-built repository
Thanks to the Amazon Cloud, with our new DPL (Debian Project Leader), Lucas Nussbaum, we rebuilt unstable last April and published it at the following address:

deb http://clang.debian.net/repository-2013-04-07/ unstable-clang main

This allows some cool stuff like:

$ echo "deb http://clang.debian.net/repository-2013-04-07/ unstable-clang main">>/etc/apt/sources.list
$ apt-get update
$ apt-get install coreutils/unstable-clang
$ ls
$ awk

Note that this repository was only one-shoot and does not get updated.

Quality of the binary produced (performance and size) can be tested thanks to this repository. Feedbacks are welcome!