cflags weirdness in gyp

I had posted a few hints for gyp and ninja usage a while ago. I still think this combination makes a great build system, but there are also a few weird things to mention. Found the solution on this gist thread and this question and answer on stackoverflow: if you want to specify c compiler flags or c++ compiler flags, you would to this via "xcode_settings". No comment.
  'make_global_settings': [
    ['CXX', '/usr/bin/clang++' ],
    # If you don't want to do this hack ...
    # ['CXX', '/usr/bin/clang++ -std=c++11' ],
  'targets': [
      'target_name': 'shc',
      'type': 'executable',
      'sources': [
        # ... omitted
      # ... you would do this. It will work with the ninja generator.
      'xcode_settings': {