I've always meant to recreate the 'makemake' utility we used to use at Acorn - none of the
current equivalents seem as good.

These tools may come in useful:

makedepend -Y *.c
gcc -M file.c
Since gcc -M lists math.h I might be able to use it to automatically add -lm ?
e.g.: gcc -M matrixmath.c|&fgrep -q /usr/include/math.h && echo \-lm

I'll get round to it eventually.