diff --git a/configure.ac b/configure.ac
index 0659008..43f79d8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -136,7 +136,7 @@ fi
 [enable_secure="1"]
 )
 if test "x$enable_secure" = "x1" ; then
-  CFLAGS="$CFLAGS -fstack-protector"
+  CFLAGS="$CFLAGS -fstack-protector-strong -fstack-clash-protection"
   LDFLAGS="$LDFLAGS -Wl,-z,relro,-z,now"

   if test "$CFLAGS" != "${CFLAGS%-O0*}" ; then # if CFLAGS contains -O0