diff --git a/vars.mk b/vars.mk
index 4ba44c8b..a4b43176 100644
--- a/vars.mk
+++ b/vars.mk
@@ -17,5 +17,5 @@ CPPFLAGS += -I$(TOPDIR)/include -D_BSD_SOURCE -D_XOPEN_SOURCE=600
 CPPFLAGS += -D_GNU_SOURCE
 WARNFLAGS ?= -pedantic -std=c99 -Wall -Wextra -Werror -Wshadow -Wformat=2
 WARNFLAGS += -Wmissing-declarations -Wcomment -Wunused-macros -Wendif-labels
-WARNFLAGS += -Wcast-qual -Wcast-align -Wconversion
-CFLAGS = $(DEBUG_FLAGS) $(WARNFLAGS) -O2 -fPIC -DPIC
+WARNFLAGS += -Wcast-qual -Wcast-align -Wconversion -Wstack-protector
+CFLAGS = $(DEBUG_FLAGS) $(WARNFLAGS) -fstack-protector-all -O2 -fPIC -DPIC