Cxref is a program that will produce documentation (in LaTeX, HTML,
RTF or SGML) including cross-references from C program source code.
It has been designed to work with ANSI C, incorporating K&R, and most
popular GNU extensions.

The documentation for the program is produced from comments in the
code that are appropriately formatted. The cross referencing comes
from the code itself and requires no extra work.

Homepage:
https://www.gedanken.org.uk/software/cxref/
