No compiler detected

I’m running OMV 4.0rc and I want to build some software that i found on Github from source.
The source code is written in C and C++ and wrapped by Cmake.
However, when I run ‘cmake .’ against the source root directory, I quickly get error messages about the absense of C and CXX compiler:

    No CMAKE_C_COMPILER could be found.
    No CMAKE_CXX_COMPILER could be found.

I have already installed GCC, GCC++ and Clang packages, but Cmake still seems to be blind.
I wonder how can I tell it to detect a compiler…