GCJ -M is producing an empty dependency list vis:

package frysk4742;
class Referee
{
    static int i;
    int j;
    Referee() {
        j = i++;
    }
}

package frysk4742;

class Referer {
    static public void main(String[] args) {
        new Referee();
    }
}

gcj -M frysk4742/Referer.java

gcc (GCC) 4.1.1 20070105 (Red Hat 4.1.1-51):
imports/tests/frysk4742/Referer.java
../../../frysk/frysk-imports/tests/frysk4742/Referer.o:  \
 ../../../frysk/frysk-imports/tests/frysk4742/Referer.java \
  /usr/share/java/libgcj-4.1.1.jar \
  ../../../frysk/frysk-imports/tests/frysk4742/Referee.java

gcc (GCC) 4.1.2 20070502 (Red Hat 4.1.2-12):
/tmp/ccSF6vYl.o: