compiling C with xref

I am working with a C program on HP-UX. I want a numbered listing with cross-reference of variables and labels. My method of compilation (my first C compilation in this environment – or anywhere for that matter) is with make on a make file full of incomprehensible stuff. I have commented out some rm lines, which I was told would help. What do I have to do to get the xref, or is this something the unix environments won’t give me?