% scons -Q hello cc -o version.o -c version.c cc -o hello.o -c hello.c cc -o hello version.o hello.o % sleep 1 % scons -Q hello cc -o version.o -c version.c scons: `hello' is up to date. % sleep 1 % [CHANGE THE CONTENTS OF hello.c] % scons -Q hello cc -o version.o -c version.c cc -o hello.o -c hello.c cc -o hello version.o hello.o % sleep 1 % scons -Q hello cc -o version.o -c version.c scons: `hello' is up to date.