+sbcl.h: $(wildcard genesis/*.h)
+ echo '#include "genesis/config.h"' >sbcl.h
+ echo '#include "genesis/constants.h"' >>sbcl.h
+
+# || true because we don't want the build to break if etags isn't there.
+# ...but it's still nice to have it done by default.
+TAGS tags: $(SRCS)
+ etags $(SRCS) || true