--- a/make.tmpl.in
+++ b/make.tmpl.in
@@ -29,7 +29,7 @@ SHELL = @SHELL@
 
 # Allow environment to override any built-in default value for CC.
 # If there is a built-in default, CC is NOT set to @CC@ here.
-CC ?= @CC@
+CC = @CC@
 
 # If $(CC) holds the usual built-in default value of 'cc' then replace it with
 # the configured value.
