--- Makefile.orig	2016-06-08 15:56:57 UTC
+++ Makefile
@@ -30,7 +30,7 @@ EXTRA_INSTALL += ./examples/hooks
 REGRESS_OPTS += --temp-config=regression.conf
 
 plhooks:
-	make -C examples/hooks USE_PGXS=1 clean install
+	${MAKE} -C examples/hooks USE_PGXS=1 clean install
 
 installcheck: plhooks
 
