diff --git a/trick_source/data_products/DPX/TESTING/DPC_TEST/makefile b/trick_source/data_products/DPX/TESTING/DPC_TEST/makefile
index dc9a4e90..d784228f 100644
--- a/trick_source/data_products/DPX/TESTING/DPC_TEST/makefile
+++ b/trick_source/data_products/DPX/TESTING/DPC_TEST/makefile
@@ -11,8 +11,8 @@ endif
 
 SHELL = /bin/sh
 RM = rm -rf
-CC ?= gcc
-CPP ?= g++
+CC = gcc
+CPP = g++
 PWD = $(shell pwd)
 DEV_NULL = > /dev/null 2>&1
 GCC = $(shell which gcc)
diff --git a/trick_source/data_products/DPX/TESTING/DPM_TEST/makefile b/trick_source/data_products/DPX/TESTING/DPM_TEST/makefile
index 9b689828..1bae65f0 100644
--- a/trick_source/data_products/DPX/TESTING/DPM_TEST/makefile
+++ b/trick_source/data_products/DPX/TESTING/DPM_TEST/makefile
@@ -3,8 +3,8 @@ include ${TRICK_HOME}/share/trick/makefiles/Makefile.common
 
 SHELL = /bin/sh
 RM = rm -rf
-CC ?= gcc
-CPP ?= g++
+CC = gcc
+CPP = g++
 PWD = $(shell pwd)
 DEV_NULL = > /dev/null 2>&1
 GCC = $(shell which gcc)
diff --git a/trick_source/data_products/DPX/TESTING/DS/makefile b/trick_source/data_products/DPX/TESTING/DS/makefile
index 719fd50b..399e0aac 100644
--- a/trick_source/data_products/DPX/TESTING/DS/makefile
+++ b/trick_source/data_products/DPX/TESTING/DS/makefile
@@ -11,8 +11,8 @@ endif
 
 SHELL = /bin/sh
 RM = rm -rf
-CC ?= gcc
-CPP ?= g++
+CC = gcc
+CPP = g++
 PWD = $(shell pwd)
 DEV_NULL = > /dev/null 2>&1
 GCC = $(shell which gcc)
diff --git a/trick_source/data_products/DPX/TESTING/DS_exercisor/makefile b/trick_source/data_products/DPX/TESTING/DS_exercisor/makefile
index 5fce401a..9c9e9be6 100644
--- a/trick_source/data_products/DPX/TESTING/DS_exercisor/makefile
+++ b/trick_source/data_products/DPX/TESTING/DS_exercisor/makefile
@@ -3,8 +3,8 @@ include ${TRICK_HOME}/share/trick/makefiles/Makefile.common
 
 SHELL = /bin/sh
 RM = rm -rf
-CC ?= gcc
-CPP ?= g++
+CC = gcc
+CPP = g++
 PWD = $(shell pwd)
 DEV_NULL = > /dev/null 2>&1
 GCC = $(shell which gcc)
diff --git a/trick_source/data_products/DPX/TESTING/TCDS/makefile b/trick_source/data_products/DPX/TESTING/TCDS/makefile
index 176ae582..cc767736 100644
--- a/trick_source/data_products/DPX/TESTING/TCDS/makefile
+++ b/trick_source/data_products/DPX/TESTING/TCDS/makefile
@@ -11,8 +11,8 @@ endif
 
 SHELL = /bin/sh
 RM = rm -rf
-CC ?= gcc
-CPP ?= g++
+CC = gcc
+CPP = g++
 PWD = $(shell pwd)
 DEV_NULL = > /dev/null 2>&1
 GCC = $(shell which gcc)
diff --git a/trick_source/data_products/DPX/TESTING/UDS/makefile b/trick_source/data_products/DPX/TESTING/UDS/makefile
index cd3225ad..c3144d8c 100644
--- a/trick_source/data_products/DPX/TESTING/UDS/makefile
+++ b/trick_source/data_products/DPX/TESTING/UDS/makefile
@@ -11,8 +11,8 @@ endif
 
 SHELL = /bin/sh
 RM = rm -rf
-CC ?= gcc
-CPP ?= g++
+CC = gcc
+CPP = g++
 PWD = $(shell pwd)
 DEV_NULL = > /dev/null 2>&1
 GCC = $(shell which gcc)
diff --git a/trick_source/data_products/DPX/test/unit_test/makefile b/trick_source/data_products/DPX/test/unit_test/makefile
index 2b087ea0..472b154e 100644
--- a/trick_source/data_products/DPX/test/unit_test/makefile
+++ b/trick_source/data_products/DPX/test/unit_test/makefile
@@ -2,8 +2,8 @@
 include ${TRICK_HOME}/share/trick/makefiles/Makefile.common
 
 RM = rm -rf
-CC ?= gcc
-CPP ?= g++
+CC = gcc
+CPP = g++
 
 DPX_DIR = ${TRICK_HOME}/trick_source/data_products/DPX
 DS_DIR  = ${TRICK_HOME}/trick_source/data_products
diff --git a/trick_source/sim_services/DataTypes/testing/makefile b/trick_source/sim_services/DataTypes/testing/makefile
index f6e27dbc..ec78b03c 100644
--- a/trick_source/sim_services/DataTypes/testing/makefile
+++ b/trick_source/sim_services/DataTypes/testing/makefile
@@ -1,7 +1,7 @@
 
 RM = rm -rf
-CC ?= cc
-CPP ?= c++
+CC = cc
+CPP = c++
 
 DECL_DIR = ..