diff --git a/tools/wrk/Makefile b/tools/wrk/Makefile
index e24b892811..bfa7827b0a 100644
--- a/tools/wrk/Makefile
+++ b/tools/wrk/Makefile
@@ -4,7 +4,7 @@ LIBS    := -lpthread -lm -lopenssl
 TARGET  := $(shell uname -s | tr [A-Z] [a-z] 2>/dev/null || echo unknown)
 
 ifeq ($(TARGET), sunos)
-	CFLAGS += -D_PTHREADS -D_POSIX_C_SOURCE=200112L
+	CFLAGS += -D_PTHREADS -D_POSIX_C_SOURCE=200112L -DBSD_COMP
 	LIBS   += -lsocket
 else ifeq ($(TARGET), darwin)
 	LDFLAGS += -pagezero_size 10000 -image_base 100000000