--- old/make/MacBundles.gmk	2019-02-05 15:44:52.970734019 +0100
+++ new/make/MacBundles.gmk	2019-02-05 15:44:52.794734019 +0100
@@ -30,7 +30,7 @@
 default: bundles
 
 # Only macosx has bundles defined.
-ifeq ($(OPENJDK_TARGET_OS), macosx)
+ifeq ($(call isTargetOs, macosx), true)
 
   bundles: jre-bundle jdk-bundle