our UNUSED macro is essentially a no-op for MSVC, which lead to the situation where this well meant macro was emitting the following warning: C4189: 'UNUSED_i': local variable is initialized but not referenced However since we have been on c++17 for a while now the UNUSED macro can be replaced with the standard [[maybe_unused]] attribute in cpp files. This changes cleans up the use of the UNUSED macro in the bf_nodes_geometry project. Differential Revision: https://developer.blender.org/D12915 Reviewed by: JacquesLucke, Severin, Sergey, HooglyBoogly