[LLVMdev] Using 'llvm-build' for out-of-tree projects

[Óscar Fuentes]

Jean-Daniel Dupas <devlists at shadowlab.org> writes:

>> P.S. Weren't we planning on removing the Make-based build system in
>> the next few months a year ago?
>
> It always lacks some important features, like building compiler-rt
> with just-built clang: http://llvm.org/bugs/show_bug.cgi?id=14109

The configure&make build works on more homogeneous environments than
CMake. Implementing the requirement you mention seems easy enough while
using toolchains where clang/clang++ works as a drop-in replacement for
the platform compiler (i.e. gcc/g++ on Linux). For the general case, it
looks quite tricky.

The feature can be implemented for the easy case (POSIX&gcc, which, most
likely, is what everybody uses) and reject it for the rest.

BTW, is compiler-rt integrated in the CMake LLVM/Clang build process, or
is it a separate step?