diff --git a/test/php/Makefile b/test/php/Makefile
index 6cc5233..10b430e 100644
--- a/test/php/Makefile
+++ b/test/php/Makefile
@@ -22,4 +22,4 @@
 	$(THRIFT) --phpi ../ThriftTest.thrift
 
 clean:
-	rm -fr gen-php gen-phpi
+	$(RM) -r gen-php gen-phpi