The value of this variable should be set prior to the first | |
:command:`project` or :command:`enable_language` command invocation | |
because it may influence configuration of the toolchain and flags. | |
It is intended to be set locally by the user creating a build tree. | |
Despite the ``OSX`` part in the variable name(s) they apply also to | |
other SDKs than macOS like iOS, tvOS, or watchOS. | |
This variable is ignored on platforms other than Apple. |