CMake Warning \(dev\) at NotCXXSourceModules.cmake:6 \(target_sources\):
  CMake's C\+\+ module support is experimental.  It is meant only for
  experimentation and feedback to CMake developers.
Call Stack \(most recent call first\):
  CMakeLists.txt:6 \(include\)
This warning is for project developers.  Use -Wno-dev to suppress it.

CMake Error in CMakeLists.txt:
  Target "not-cxx-source" contains the source

    .*/Tests/RunCMake/CXXModules/sources/c-anchor.c

  in a file set of type "CXX_MODULES" but the source is not classified as a
  "CXX" source.


CMake Generate step failed.  Build files cannot be regenerated correctly.