[baradejoo]

Goal

Enable the realsense2_camera and realsense2_description packages on macOS in the robostack-lyrical distribution.

Description

realsense2_camera and realsense2_description were previously built only on Linux. The underlying librealsense library is available on conda-forge for macOS, so the only blocker was a build failure of realsense2_camera on macOS.

During local testing on macOS (osx-arm64), the build failed at the linking stage with:
ld: unknown option: -z. The root cause is in the "Compiler Defense Flags" block of upstream CMakeLists.txt: for the Clang compiler it unconditionally adds -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now. These are GNU ELF linker options and are not supported by the Apple linker (ld64). Conda-forge's clang on macOS reports itself as Clang, so it enters that branch.

Solution

This PR includes a one-line patch that skips the -z linker flags on Apple:

elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang" AND NOT APPLE)

This ensures:

• the hardening flags are still used on Linux (both GCC and Clang),
• the build succeeds on macOS (osx-64 and osx-arm64),
• the patch is a no-op on other platforms, so it is kept as a generic patch/ros-lyrical-realsense2-camera.patch (same approach as apriltag_ros).

Changes

• Moved realsense2_camera and realsense2_description from the Linux-only section to the not win section in vinca.yaml.
• Added patch/ros-lyrical-realsense2-camera.patch skipping the -z linker flags on Apple.

License

realsense2_camera is licensed under the Apache-2.0 license.

This PR does not modify upstream functionality beyond RoboStack packaging integration and a minimal build-system portability fix.

Notes

Build tested locally on osx-arm64 (ros2-realsense2-camera, ros2-realsense2-camera-msgs, ros2-realsense2-description), all tests passed. Linux and osx-64 will be verified by CI.

The proper upstream fix would be to guard the -z flags with NOT APPLE in realsense-ros itself.