Specify gcc -pg option for catkin?

Hi all, I am working on a project to do some performance profiling on amcl. To do this, I want to use gprof. To use gprof, I need to compile amcl with the -pg option for gcc. How can I do this in the catkin environment? Is this the right approach? Bonus question: I don't really want to profile all of the navigation package, only amcl. How can I break amcl out of the navigation package so that I am only profiling amcl? thanks in advance! dw