Option De-duplication

Option De-duplication ^^^^^^^^^^^^^^^^^^^^^

The final set of options used for a target is constructed by accumulating options from the current target and the usage requirements of its dependencies. The set of options is de-duplicated to avoid repetition.

.. versionadded:: 3.12 While beneficial for individual options, the de-duplication step can break up option groups. For example, -option A -option B becomes -option A B. One may specify a group of options using shell-like quoting along with a SHELL: prefix. The SHELL: prefix is dropped, and the rest of the option string is parsed using the :command:separate_arguments UNIX_COMMAND mode. For example, "SHELL:-option A" "SHELL:-option B" becomes -option A -option B.