On 2014-11-01 at 17:26:26 +0100, Austin Seipp wrote: [...]
How long does building those two llvm binaries take? If it is sufficiently quick, maybe that would be a suitable distribution for developers as well, and avoids having to separately build, distribute, download, and install the binaries.
In practice it takes a while... I haven't timed it, but I'd guess on average it adds about 30-40 minutes for most people just to build llvm. I'm not sure how many things we can disable to make the build faster, but I'd ballpark it at half an hour at best (it's a few thousand source files, after all).
This would mostly hurt if you cleaned up the tree later (e.g. 'make distclean'), which I do rather frequently in order to get a pristine build tree.
This also hurts buildbots as 30+ minutes is even more than a validate run takes... :-/ Otoh, we don't have to force everyone to build GHC's bundled LLVM, and could allow to use the system-wide installed LLVM binaries if a matching version is provided by the system. As an example, I currently have llvm-3.4 and llvm-3.5 installed, and could easily have a llvm-3.6 snapshot installed via the package manager (e.g. via http://llvm.org/apt/). Cheers, hvr