diff --git a/unix/Makefile.in b/unix/Makefile.in
index bc73118..9c237ea 100644
--- a/unix/Makefile.in
+++ b/unix/Makefile.in
@@ -1357,7 +1357,7 @@ bncore.o: $(TOMMATH_DIR)/bncore.c $(MATHHDRS)
 bn_reverse.o: $(TOMMATH_DIR)/bn_reverse.c $(MATHHDRS)
 	$(CC) -c $(CC_SWITCHES) $(TOMMATH_DIR)/bn_reverse.c
 
-bn_fast_s_mp_mul_digs.o: $(TOMMATH_DIR)/bn_fast_s_mp_mul_digs.c $(MATHHDRS)
+bn_fast_s_mp_mul_digs.o: $(TOMMATH_DIR)/bn_fast_s_mp_mul_digs.c $(MATHHDRS) $(DTRACE_HDR)
 	$(CC) -c $(CC_SWITCHES) $(TOMMATH_DIR)/bn_fast_s_mp_mul_digs.c
 
 bn_fast_s_mp_sqr.o: $(TOMMATH_DIR)/bn_fast_s_mp_sqr.c $(MATHHDRS)