Hello,
in my system I have installed both llvm and clang as standalone applications. I was wondering whether it is possible to build cling using them, without downloading whole llvm and clang repositories, like shown on this page: root.cern.ch/cling-build-instructions
Currently both llvm and clang are in 3.7.0 version.
Rafal
Hi,
It’s not. We have patches that transform llvm + clang into something that works for an interpreter. We are still planning to back-feed these patches, but for now you’ll have to use our branches.
Cheers, Axel.
Is there any update of back-feed process? Compile with whole LLVM is really a big problem for PC.
How is it a “big problem”? Do you mean it takes a lot of time? Is using ROOT binaries a reasonable work-around?
“big problem” is likely not the best wording, but having experienced it myself, I would say that it is a fairly “heavy task”. Also the whole llvm+clang+cling compiled package (including headers and dev tools) is around 1 GB for me. How much slimmer would a cling install relying on the system llvm be, maybe 10-to-100 times?
Cling is so much more than “the ROOT engine”. Many people outside HEP have little-to-no interest in ROOT, yet they make great uses of cling (and of the www 
).
I have this dream of having cling under the llvm umbrella, with integrated development cycles, shipping on the side of clang with the same feature support 
Hi Dario,
Having cling part of the llvm tools universe would be great. I doubt it will happen anytime soon as we - sadly - don’t have the resources for it: in the fight sustainability versus acute problems, sustainability always comes in second.
As I said, installing ROOT can be seen as a workaround.
Cheers, Axel