How to export non-standard include directories in catkin?

This question spawned from question 68680. I'm using yujin_tools to cross-compile ROS for ARM. I've created a Catkin package for tinyxml that installs headers to /include/tinyxml, and the package advertises "include" and "include/tinyxml" in the catkin_package() macro. When I build rospack, it complains about not finding the tinyxml.h header: /home/user/ros_yujin_ws/src/rospack/src/rospack.cpp:30: fatal error: tinyxml.h: No such file or directory rospack is using the non-namespaced version of the tinyxml include directive, but I've installed them namespaced. How do I tell rospack to look in /include/tinyxml instead of or in addition to /include?