Developing are reaching a point where the mainline LLVM/Clang compiler in an "out of the box" configuration can compile the mainline Linux kernel with only a few patches against the kernel's source tree. This summer's release of LLVM/Clang 3.3 should be a big milestone...
April 18, 2013
LLVM/Clang 3.3 Should Be Close To Building Linux Kernel
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