diff --git a/make_helpers/defaults.mk b/make_helpers/defaults.mk
index 578bd59..9e5fe85 100644
--- a/make_helpers/defaults.mk
+++ b/make_helpers/defaults.mk
@@ -19,6 +19,9 @@
 # The Target build architecture. Supported values are: aarch64, aarch32.
 ARCH				:= aarch64
 
+# ARM Architecture feature modifiers: none by default
+ARM_ARCH_FEATURE		:= none
+
 # ARM Architecture major and minor versions: 8.0 by default.
 ARM_ARCH_MAJOR			:= 8
 ARM_ARCH_MINOR			:= 0