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).
The OLD behaviors of all policies are deprecated, but only by
documentation. Add an explicit deprecation diagnostic for some policies
to encourage projects to port away from setting policies to OLD.
In commit v3.5.0-rc1~8^2~2 (Help: Clarify policy `CMP0040`
documentation, 2016-01-28) the documentation was clarified to indicate
that the target must be defined in the current directory. Do the same
for the text of the policy warning itself.
Fixes: #17399
Run the `Utilities/Scripts/clang-format.bash` script to update
all our C++ code to a new style defined by `.clang-format`.
Use `clang-format` version 3.8.
* If you reached this commit for a line in `git blame`, re-run the blame
operation starting at the parent of this commit to see older history
for the content.
* See the parent commit for instructions to rebase a change across this
style transition commit.
The add_custom_command(TARGET) signature only works for targets defined
in the current directory. Clarify this in the error message when the
target exists but was defined elsewhere.
Inspired-by: Bartosz Kosiorek <gang65@poczta.onet.pl>
