GNU cflow analyzes a collection of C source files and prints a graph,
charting control flow within the program.

GNU cflow is able to produce both direct and inverted flowgraphs for C
sources. Optionally a cross-reference listing can be generated. Two
output formats are implemented: POSIX and GNU (extended).

Input files can optionally be preprocessed before analyzing.

Homepage:
https://www.gnu.org/software/cflow/
