| .. note:: | |
| If the compiler's default standard level is at least that | |
| of the requested feature, CMake may omit the ``-std=`` flag. | |
| The flag may still be added if the compiler's default extensions mode | |
| does not match the :prop_tgt:`<LANG>_EXTENSIONS` target property, | |
| or if the :prop_tgt:`<LANG>_STANDARD` target property is set. |