CMAKE_<LANG>_FLAGS
------------------

Flags for all build types.

``<LANG>`` flags used regardless of the value of :variable:`CMAKE_BUILD_TYPE`.

This is initialized for each language from environment variables:

* ``CMAKE_C_FLAGS``:
  Initialized by the :envvar:`CFLAGS` environment variable.
* ``CMAKE_CXX_FLAGS``:
  Initialized by the :envvar:`CXXFLAGS` environment variable.
* ``CMAKE_CUDA_FLAGS``:
  Initialized by the :envvar:`CUDAFLAGS` environment variable.
* ``CMAKE_Fortran_FLAGS``:
  Initialized by the :envvar:`FFLAGS` environment variable.

This value is a command-line string fragment. Therefore, multiple options
should be separated by spaces, and options with spaces should be quoted.

The flags in this variable will be passed to the compiler before those
in the per-configuration :variable:`CMAKE_<LANG>_FLAGS_<CONFIG>` variant,
and before flags added by the :command:`add_compile_options` or
:command:`target_compile_options` commands.