diff --git a/lowpan/tests/Android.mk b/lowpan/tests/Android.mk
index 9043672..0042ff9 100644
--- a/lowpan/tests/Android.mk
+++ b/lowpan/tests/Android.mk
@@ -34,10 +34,6 @@
 # This only works if the class name matches the file name and the directory structure
 # matches the package.
 local_classes := $(subst /,.,$(patsubst src/%.java,%,$(local_java_files)))
-# Utility variables to allow replacing a space with a comma
-comma:= ,
-empty:=
-space:= $(empty) $(empty)
 # Convert class name list to jacoco exclude list
 # This appends a * to all classes and replace the space separators with commas.
 # These patterns will match all classes in this module and their inner classes.
diff --git a/wifi/tests/Android.mk b/wifi/tests/Android.mk
index 8804c8a..3d535f0 100644
--- a/wifi/tests/Android.mk
+++ b/wifi/tests/Android.mk
@@ -34,10 +34,6 @@
 # This only works if the class name matches the file name and the directory structure
 # matches the package.
 local_classes := $(subst /,.,$(patsubst src/%.java,%,$(local_java_files)))
-# Utility variables to allow replacing a space with a comma
-comma:= ,
-empty:=
-space:= $(empty) $(empty)
 # Convert class name list to jacoco exclude list
 # This appends a * to all classes and replace the space separators with commas.
 # These patterns will match all classes in this module and their inner classes.