Adding suffix ".c"
Adding suffix ".d"
defining transformation from `.c' to `.d'
inserting ".c" (1) at end of list
inserting ".d" (2) at end of list
Adding suffix ".e"
defining transformation from `.d' to `.e'
inserting ".d" (2) at end of list
inserting ".e" (3) at end of list
Adding suffix ".f"
defining transformation from `.e' to `'
inserting ".e" (3) at end of list
inserting "" (0) at end of list
defining transformation from `.e' to `.f'
inserting ".e" (3) at end of list
inserting ".f" (4) at end of list
defining transformation from `.f' to `.e'
inserting ".f" (4) at end of list
inserting ".e" (3) at end of list
make: "suff-transform-endless.mk" line 38: prevent endless loop

make: stopped in unit-tests
exit status 1