In general we disallow references to transitive target properties, such
as `COMPILE_DEFINITIONS`, in `[INTERFACE_]LINK_LIBRARIES` properties,
because the latter establish the transitivity itself. Prior to CMP0189,
the `[INTERFACE_]LINK_LIBRARIES` properties were not themselves transitive
in `$<TARGET_PROPERTY>` expressions, so existing projects have code like
target_link_libraries(foo PRIVATE "$<TARGET_PROPERTY:tgt,LINK_LIBRARIES>")
Policy CMP0189's NEW behavior, introduced by commit b3da9c6d60 (GenEx:
Evaluate LINK_LIBRARIES target properties transitively, 2025-02-24,
v4.1.0-rc1~731^2), makes `$<TARGET_PROPERTY:tgt,LINK_LIBRARIES>`
transitive, causing the above to be rejected. Since evaluation of a
target's link libraries can already encounter and handle other targets'
link libraries, allow it in this case.
Fixes: #27265
Since commit 84db8506ff (Deprecate compatibility with CMake versions older
than 3.10, 2024-10-03, v3.31.0-rc1~23^2) the `cmake_minimum_required` and
`cmake_policy` commands warn if the project does not enable policies as
of 3.10 or higher. Clarify the advice given in the warning message about
how to update the version specification, particularly without actually
requiring a newer minimum version of CMake.
Issue a deprecation warning on calls to `cmake_minimum_required` or
`cmake_policy` that set policies based on versions older than 3.10.
Note that the effective policy version includes `...<max>` treatment.
Update the check from commit 3a4791548d (Deprecate compatibility with
CMake versions older than 3.5, 2023-02-09, v3.27.0-rc1~508^2).
In commit bbba701899 (Link properties: must be transitive over private
dependency on static library, 2019-12-06, v3.17.0-rc1~323^2) and
commit af9d4f24ae (Link properties: must be transitive over private
dependency on static library, 2019-12-11, v3.17.0-rc1~305^2) we
neglected to implement CMP0099 NEW behavior for `TARGET_PROPERTY`
evaluation. Add policy CMP0166 to fix this.
Issue a deprecation warning on calls to `cmake_minimum_required` or
`cmake_policy` that set policies based on versions older than 3.5.
Note that the effective policy version includes `...<max>` treatment.
Update the check from commit 5845c218d7 (Deprecate compatibility with
CMake versions older than 2.8.12, 2020-06-12, v3.19.0-rc1~629^2).
For policy-specific tests, use the version before the policy was
introduced. Otherwise, use 3.5 where possible.
Also, remove `cmake_minimum_required()` and `project()` calls from
individual cases where they are handled by `CMakeLists.txt`.
When `$<TARGET_PROPERTY:tgt,prop>` is used in an `INTERFACE_*` target
property for usage requirements, it may be evaluated in the context of a
dependent target in another directory. Look up the `tgt` name in the
directory of the target whose property holds the expression so that
imported targets isolated to that directory are visible.
Fixes: #24163
The existing cases all need to enable a language. Move this out of the
`CMakeLists.txt` file and into the individual cases to make room for
other cases that may not need this.