Thanks! On the Windows side we probably need to add a definition of the _USE_MATH_DEFINES macro.

Interesting failure %SRC_DIR%\ros-humble-apriltag-mit\src\work\src\TagFamily.cc(107): error C3861: '__builtin_popcountll': identifier not found I don't really need apriltag-mit so I can remove it too if the fix is not straightforward for windows. What do you think @traversaro ?

You could probably patch windows with something like:

https://stackoverflow.com/a/24550632

#ifdef _MSC_VER
#  include <intrin.h>
#  define __builtin_popcount __popcnt
#endif

Although IDK if that works for popcount_ll

It seems there is a simple portable implementation of that function in llvm's libcxx, we may think of using it.

It seems there is a simple portable implementation of that function in llvm's libcxx, we may think of using it.

https://github.com/llvm/llvm-project/blob/7f4422d99115efbb770e13ccb60cf6bfc190c245/llvm/include/llvm/ADT/bit.h#L372

All the apriltag_detector have unconditional add_compile_options that only make sense on GCC and Clang, not on MSVC: https://github.com/search?q=repo%3Aros-misc-utilities%2Fapriltag_detector%20Wextra&type=codem as done in https://github.com/ros2/rosidl/blob/dfdff27ea6231a39333c64a796c15fd3b7c4f839/rosidl_runtime_cpp/CMakeLists.txt#L71-L73, or simply not added on Windows.

Thanks!