digraph G {
	foo_o [label="foo.o"];
	bar_o [label="bar.o"];
	foo_h [label="foo.h"];
	cmd1 [label="gcc -c foo.c -o foo.o" shape="rectangle"];
	cmd2 [label="gcc -c bar.c -o bar.o" shape="rectangle"];
	foo_o -> {cmd1} [dir="back"];
	bar_o -> {cmd2} [dir="back"];
	{cmd1 cmd2} -> foo_h [dir="back"];
}
