CMake warning with 3.20

[vadi2]

Modern CMake is giving the following warning on configure:

CMake Deprecation Warning at 3rdparty/edbee-lib/vendor/qslog/CMakeLists.txt:2 (cmake_minimum_required):
  Compatibility with CMake < 2.8.12 will be removed from a future version of
  CMake.

  Update the VERSION argument <min> value or use a ...<max> suffix to tell
  CMake that the project does not need compatibility with older versions.

[gamecreature]

There are several other CMake issues. I've once merged a CMake configuration via a merge request.
But I don't use it myself.

[gamecreature]

Just tried to run it. It completely fails on OS X. (more then a warning)

-- The C compiler identification is AppleClang 12.0.0.12000032
-- The CXX compiler identification is AppleClang 12.0.0.12000032
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - failed
-- Check for working C compiler: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/cc
-- Check for working C compiler: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/cc - broken
CMake Error at /usr/local/Cellar/cmake/3.19.6/share/cmake/Modules/CMakeTestCCompiler.cmake:66 (message):
  The C compiler

    "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/cc"

  is not able to compile a simple test program.

[vadi2]

That's a bit weird - we use the same compiler (with ccache) and it does build fine:

  -- The C compiler identification is AppleClang 12.0.0.12000032
  -- The CXX compiler identification is AppleClang 12.0.0.12000032
  -- Detecting C compiler ABI info
  -- Detecting C compiler ABI info - done
  -- Check for working C compiler: /usr/local/opt/ccache/libexec/cc - skipped
  -- Detecting C compile features
  -- Detecting C compile features - done
  -- Detecting CXX compiler ABI info
  -- Detecting CXX compiler ABI info - done
  -- Check for working CXX compiler: /usr/local/opt/ccache/libexec/c++ - skipped
  -- Detecting CXX compile features
  -- Detecting CXX compile features - done