diff --git a/openair2/LAYER2/Makefile b/openair2/LAYER2/Makefile
index d703281df780137b533a7ed8b8fd95bd21f2e1c9..5890cd548e684fa559e2abf2aa4efad778dfa6a6 100644
--- a/openair2/LAYER2/Makefile
+++ b/openair2/LAYER2/Makefile
@@ -11,8 +11,8 @@
 
 include $(OPENAIR_HOME)/common/utils/Makefile.inc
 
-KERNEL_ARCH=$(shell echo `uname -m`)
-SET_X64=$(shell if [ $(KERNEL_ARCH) = 'x86_64' ]; then echo true ; fi)
+KERNEL_ARCH:=$(shell echo `uname -m`)
+SET_X64:=$(shell if [ $(KERNEL_ARCH) = 'x86_64' ]; then echo true ; fi)
 ifdef RTAI
 # Get the RTAI variables
 CCC = $(shell rtai-config --cc)