diff --git a/bacnet-stack/demo/dcc/Makefile b/bacnet-stack/demo/dcc/Makefile
index 6eaec7ef..d7b3abc6 100644
--- a/bacnet-stack/demo/dcc/Makefile
+++ b/bacnet-stack/demo/dcc/Makefile
@@ -1,5 +1,5 @@
 #Makefile to build BACnet Application for GCC compiler
-CC      = gcc
+CC := gcc
 
 TARGET = bacdcc
 
diff --git a/bacnet-stack/demo/epics/Makefile b/bacnet-stack/demo/epics/Makefile
index b91288e2..029a2807 100644
--- a/bacnet-stack/demo/epics/Makefile
+++ b/bacnet-stack/demo/epics/Makefile
@@ -1,5 +1,5 @@
 #Makefile to build BACnet Application for the Linux Port
-CC      = gcc
+CC := gcc
 
 TARGET = bacepics
 
diff --git a/bacnet-stack/demo/iamrouter/Makefile b/bacnet-stack/demo/iamrouter/Makefile
index d4176f7f..ce64ff7d 100644
--- a/bacnet-stack/demo/iamrouter/Makefile
+++ b/bacnet-stack/demo/iamrouter/Makefile
@@ -1,5 +1,5 @@
 #Makefile to build BACnet Application for the Linux Port
-CC = gcc
+CC := gcc
 
 TARGET = baciamr
 
diff --git a/bacnet-stack/demo/initrouter/Makefile b/bacnet-stack/demo/initrouter/Makefile
index 9aad7dd2..74b0ac35 100644
--- a/bacnet-stack/demo/initrouter/Makefile
+++ b/bacnet-stack/demo/initrouter/Makefile
@@ -1,5 +1,5 @@
 #Makefile to build BACnet Application for the Linux Port
-CC = gcc
+CC := gcc
 
 TARGET = bacinitr
 
diff --git a/bacnet-stack/demo/mstpcap/Makefile b/bacnet-stack/demo/mstpcap/Makefile
index 65e64629..6b2d4454 100644
--- a/bacnet-stack/demo/mstpcap/Makefile
+++ b/bacnet-stack/demo/mstpcap/Makefile
@@ -1,7 +1,7 @@
 #Makefile to build BACnet Application for the Linux Port
 
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = mstpcap
 
diff --git a/bacnet-stack/demo/readfile/Makefile b/bacnet-stack/demo/readfile/Makefile
index a89efbec..8dd87335 100644
--- a/bacnet-stack/demo/readfile/Makefile
+++ b/bacnet-stack/demo/readfile/Makefile
@@ -1,5 +1,5 @@
 #Makefile to build BACnet Application for the Linux Port
-CC = gcc
+CC := gcc
 
 TARGET = bacarf
 
diff --git a/bacnet-stack/demo/readprop/Makefile b/bacnet-stack/demo/readprop/Makefile
index 096156f9..1c0b1c1b 100644
--- a/bacnet-stack/demo/readprop/Makefile
+++ b/bacnet-stack/demo/readprop/Makefile
@@ -1,6 +1,6 @@
 #Makefile to build BACnet Application using GCC compiler
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacrp
 
diff --git a/bacnet-stack/demo/readpropm/Makefile b/bacnet-stack/demo/readpropm/Makefile
index 3907b3ce..c47dd8cd 100644
--- a/bacnet-stack/demo/readpropm/Makefile
+++ b/bacnet-stack/demo/readpropm/Makefile
@@ -1,6 +1,6 @@
 #Makefile to build BACnet Application for the Linux Port
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacrpm
 
diff --git a/bacnet-stack/demo/reinit/Makefile b/bacnet-stack/demo/reinit/Makefile
index 1d44efd1..c7141a51 100644
--- a/bacnet-stack/demo/reinit/Makefile
+++ b/bacnet-stack/demo/reinit/Makefile
@@ -1,7 +1,7 @@
 #Makefile to build BACnet Application for the Linux Port
 
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacrd
 
diff --git a/bacnet-stack/demo/server/Makefile b/bacnet-stack/demo/server/Makefile
index af7945fc..289fbdd1 100644
--- a/bacnet-stack/demo/server/Makefile
+++ b/bacnet-stack/demo/server/Makefile
@@ -1,7 +1,7 @@
 #Makefile to build BACnet Application for the Linux Port
 
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacserv
 
diff --git a/bacnet-stack/demo/timesync/Makefile b/bacnet-stack/demo/timesync/Makefile
index 1919ba31..7e44af77 100644
--- a/bacnet-stack/demo/timesync/Makefile
+++ b/bacnet-stack/demo/timesync/Makefile
@@ -1,7 +1,7 @@
 #Makefile to build BACnet Application for the Linux Port
 
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacts
 
diff --git a/bacnet-stack/demo/ucov/Makefile b/bacnet-stack/demo/ucov/Makefile
index 24ee6a0b..b9c9d05d 100644
--- a/bacnet-stack/demo/ucov/Makefile
+++ b/bacnet-stack/demo/ucov/Makefile
@@ -1,7 +1,7 @@
 #Makefile to build BACnet Application for the Linux Port
 
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacucov
 
diff --git a/bacnet-stack/demo/whohas/Makefile b/bacnet-stack/demo/whohas/Makefile
index 2bc620ac..3198af0a 100644
--- a/bacnet-stack/demo/whohas/Makefile
+++ b/bacnet-stack/demo/whohas/Makefile
@@ -1,7 +1,7 @@
 #Makefile to build BACnet Application for the Linux Port
 
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacwh
 
diff --git a/bacnet-stack/demo/whois/Makefile b/bacnet-stack/demo/whois/Makefile
index fb643ac6..7c240951 100644
--- a/bacnet-stack/demo/whois/Makefile
+++ b/bacnet-stack/demo/whois/Makefile
@@ -1,5 +1,5 @@
 #Makefile to build BACnet Application for the Linux Port
-CC = gcc
+CC := gcc
 
 TARGET = bacwi
 
diff --git a/bacnet-stack/demo/whoisrouter/Makefile b/bacnet-stack/demo/whoisrouter/Makefile
index 2cae3320..6cb8d003 100644
--- a/bacnet-stack/demo/whoisrouter/Makefile
+++ b/bacnet-stack/demo/whoisrouter/Makefile
@@ -1,5 +1,5 @@
 #Makefile to build BACnet Application for the Linux Port
-CC = gcc
+CC := gcc
 
 TARGET = bacwir
 
diff --git a/bacnet-stack/demo/writefile/Makefile b/bacnet-stack/demo/writefile/Makefile
index 99de6aea..4fe4810f 100644
--- a/bacnet-stack/demo/writefile/Makefile
+++ b/bacnet-stack/demo/writefile/Makefile
@@ -1,7 +1,7 @@
 #Makefile to build BACnet Application for the Linux Port
 
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacawf
 
diff --git a/bacnet-stack/demo/writeprop/Makefile b/bacnet-stack/demo/writeprop/Makefile
index 934959fe..c7e517de 100644
--- a/bacnet-stack/demo/writeprop/Makefile
+++ b/bacnet-stack/demo/writeprop/Makefile
@@ -1,7 +1,7 @@
 #Makefile to build BACnet Application for the Linux Port
 
 # Compiler to use
-CC = gcc
+CC := gcc
 # Executable file name
 TARGET = bacwp
 
diff --git a/bacnet-stack/lib/Makefile b/bacnet-stack/lib/Makefile
index eadd7a9a..d66776f6 100644
--- a/bacnet-stack/lib/Makefile
+++ b/bacnet-stack/lib/Makefile
@@ -1,10 +1,10 @@
 #Makefile to build BACnet Library with GCC
 
 # tools 
-#     ('?=' sets them to gcc and ar unless they are already defined for
+#     (':=' sets them to gcc and ar unless they are already defined for
 #           a board-specific cross-compiler and archiver)
-CC ?= gcc
-AR ?= ar
+CC := gcc
+AR := ar
 
 # target
 TARGET = bacnet