Properties defined at build-time do not seem to be inherited by "modules" included via medusa.cmake

[RomanHargrave]

Currently, I can not build medusa out of the box due to CMake being stuck on LLVM_ROOT not being defined when building compil.

When LLVM_ROOT is defined when invoking cmake (... -DLLVM_ROOT=/usr/lib/llvm-3.9) its definition is not passed on to the cmake build for compil, and furthermore it appears to have been ignored by cmake, since it's not in CMakeCache.txt.

[wisk]

Hi Roman,

The build system is currently broken. I might overcome something, but normally LLVM_ROOT is not mandatory to use Medusa.
Do you need this compil_llvm? This module is quite recent (compared to the others) and probably not stable.