diff --git a/Makefile.system b/Makefile.system
index 3c29ab3f3..7b4c70ef7 100644
--- a/Makefile.system
+++ b/Makefile.system
@@ -419,7 +419,7 @@ ifeq ($(OSNAME), AIX)
 EXTRALIB	+= -lm
 endif
 
-ifeq ($(OSNAME), FreeBSD)
+ifeq ($(OSNAME), $(filter $(OSNAME),FreeBSD OpenBSD NetBSD DragonFly)
 ifeq ($(ARCH), $(filter $(ARCH),arm arm64))
 EXTRALIB	+= -lm
 endif