diff --git a/m4/fp_cpp_cmd_with_args.m4 b/m4/fp_cpp_cmd_with_args.m4
index f806267270488b05520209529badd645c39b42e2..eebeeb203f88e7b4ac8dc616b0ebc41ce095b4c1 100644
--- a/m4/fp_cpp_cmd_with_args.m4
+++ b/m4/fp_cpp_cmd_with_args.m4
@@ -51,7 +51,7 @@ AC_ARG_WITH(cpp-flags,
 [
   # Augment CPP_ARGS with whatever flags were previously configured and passed
   # as an argument.
-  CPP_ARGS="$CPP_ARGS $$3"
+  CPP_ARGS="$$3 $CPP_ARGS"
 ])
 
 $2="$CPP_CMD"