--- a/make/autoconf/flags-cflags.m4	Tue Jan 15 16:40:31 2019 -0500
+++ b/make/autoconf/flags-cflags.m4	Tue Jan 15 22:54:09 2019 +0100
@@ -527,8 +527,8 @@
   fi
 
   if test "x$TOOLCHAIN_TYPE" = xgcc; then
-    TOOLCHAIN_CFLAGS_JVM="$TOOLCHAIN_CFLAGS_JVM -fcheck-new"
-    TOOLCHAIN_CFLAGS_JDK="-pipe"
+    TOOLCHAIN_CFLAGS_JVM="$TOOLCHAIN_CFLAGS_JVM -fcheck-new -fstack-protector"
+    TOOLCHAIN_CFLAGS_JDK="-pipe -fstack-protector"
     TOOLCHAIN_CFLAGS_JDK_CONLY="-fno-strict-aliasing" # technically NOT for CXX (but since this gives *worse* performance, use no-strict-aliasing everywhere!)
 
     CXXSTD_CXXFLAG="-std=gnu++98"