[poly2tri] Set policy CMP0063 to NEW

[kduske]

Describe the pull request

• What does your PR fix?

Linker warnings about conflicting visibility settings if poly2tri, which is built as a static library, is pulled into a build as an indirect dependency of a shared library. An example of such a configuration is assimp, which depends on poly2tri, and can be built as a dynamic library on macOS.

Policy CMP0063 enables CMake to set the symbol visibility of static libraries to avoid this problem.

• Which triplets are supported/not supported? Have you updated the CI baseline?

  all, No

• Does your PR follow the maintainer guide?

  Yes, to the best of my knowledge.

• If you have added/updated a port: Have you run ./vcpkg x-add-version --all and committed the result?

No, the maintainer guide says to do that only when updating multiple ports at the same time.

[kduske]

@microsoft-github-policy-service agree]

[kduske]

@microsoft-github-policy-service agree

[Neumann-A]

Just push this to 3.15 or higher. (vcpkg internally has 3.24)

[kduske]

Do you mean instead of or in addition to setting the policy?

[dg0yt]

Do you mean instead of or in addition to setting the policy?

"instead".
By requiring a particular version, CMake sets all policies introduced up to that version to NEW. Version 3.15 implicitly includes CMP0063 from CMake 3.3.
(PS Bumping cmake_minimum_required may come with side effects, but @Neumann-A probably hopes for vcpkg-CI to catch them.)

[kduske]

Unfortunately that does not fix the issue. As per the documentation, this particular policy defaults to OLD if not set even on 3.25.

[Neumann-A]

CMake version 3.24.2 warns when the policy is not set and uses OLD behavior

do you get the warning ? Are the properties even getting set?

[kduske]

I get the warning if I set

set(CMAKE_CXX_VISIBILITY_PRESET hidden)
set(CMAKE_VISIBILITY_INLINES_HIDDEN TRUE)

in poly2tri's CMakeList.txt, but not the policy. And this reveals an error I made in the initial PR, where I did not set the visibility preset properties. I'm having a bit of trouble with my setup locally so I did not notice that it doesn't work when I only set the policy.

Here's the exact warning I get:

CMake Warning (dev) at /Users/kristian/Documents/Code/TrenchBroom/vcpkg/scripts/buildsystems/vcpkg.cmake:613 (_add_library):
  Policy CMP0063 is not set: Honor visibility properties for all target
  types.  Run "cmake --help-policy CMP0063" for policy details.  Use the
  cmake_policy command to set the policy and suppress this warning.

  Target "poly2tri" of type "STATIC_LIBRARY" has the following visibility
  properties set for CXX:

    CXX_VISIBILITY_PRESET
    VISIBILITY_INLINES_HIDDEN

  For compatibility CMake is not honoring them for this target.
Call Stack (most recent call first):
  CMakeLists.txt:38 (add_library)
This warning is for project developers.  Use -Wno-dev to suppress it.

[kduske]

I'll push some fixup to address all these issues.

[kduske]

Ok, 06c684f should fix these issues now. I have not updated the required cmake version to keep the changes minimal. I think it's not necessary to bump it for this. Let me know if you think otherwise and I'll change it.

[github-actions]

Use the version scheme "version-date" instead of "version-string" in port "poly2tri".

You have modified or added at least one vcpkg.json where you should check the license field.

If you feel able to do so, please consider adding a "license" field to the following files:

• ports/poly2tri/vcpkg.json

Valid values for the license field can be found in the documentation

[github-actions]

You have modified or added at least one vcpkg.json where you should check the license field.

If you feel able to do so, please consider adding a "license" field to the following files:

• ports/poly2tri/vcpkg.json

Valid values for the license field can be found in the documentation

[BillyONeal]

Thanks for running down that extremely bizarre policy thing