| CMake uses this environment variable value, in combination with its own | |
| builtin default flags for the toolchain, to initialize and store the | |
| |CMAKE_LANG_FLAGS| cache entry. | |
| This occurs the first time a build tree is configured for language |LANG|. | |
| For any configuration run (including the first), the environment variable | |
| will be ignored if the |CMAKE_LANG_FLAGS| variable is already defined. |