[LLVMdev] Using thin archives when building llvm

[Rafael Espíndola]

> It is generally useful. The gnu ar already supports it. The
> implementation in llvm-ar is compatible with it.
>
> Making it available in llvm-lib is an extension over lib.exe.

I was able to get this to work on windows by using

-DCMAKE_STATIC_LINKER_FLAGS=/llvmlibthin

Thanks,
Rafael