New in version 3.14.
$<IN_LIST:...> handles empty list items.
In CMake 3.13 and lower, the
$<IN_LIST:...> generator expression always
0 if the first argument was empty, even if the list contained an
empty item. This behavior is inconsistent with the
IN_LIST behavior of
if(), which this generator expression is meant to emulate. CMake 3.14
and later handles this case correctly.
OLD behavior of this policy is for
$<IN_LIST:...> to always return
0 if the first argument is empty. The
NEW behavior is to return
if the first argument is empty and the list contains an empty item.
This policy was introduced in CMake version 3.14. CMake version
3.26.20230330-g57bb7e6 warns when the policy is not set and uses
cmake_policy() command to set it to
OLD behavior of a policy is
deprecated by definition
and may be removed in a future version of CMake.