--- a/make/launcher/Launcher-java.base.gmk	Tue Feb 05 10:24:39 2019 +0100
+++ b/make/launcher/Launcher-java.base.gmk	Tue Feb 05 14:57:24 2019 +0100
@@ -51,7 +51,7 @@
 
 TARGETS += $(SUPPORT_OUTPUTDIR)/modules_cmds/java.base/java$(EXE_SUFFIX)
 
-ifeq ($(OPENJDK_TARGET_OS), windows)
+ifeq ($(call isTargetOs, windows), true)
   $(eval $(call SetupBuildLauncher, javaw, \
       CFLAGS := -DJAVAW -DEXPAND_CLASSPATH_WILDCARDS -DENABLE_ARG_FILES, \
       EXTRA_RC_FLAGS := $(JAVA_RC_FLAGS), \
@@ -65,7 +65,7 @@
 
 ################################################################################
 
-ifeq ($(OPENJDK_TARGET_OS), linux)
+ifeq ($(call isTargetOs, linux), true)
   $(eval $(call SetupJdkExecutable, BUILD_JEXEC, \
       NAME := jexec, \
       SRC := $(TOPDIR)/src/$(MODULE)/unix/native/launcher, \
@@ -84,7 +84,7 @@
 
 ################################################################################
 
-ifneq ($(findstring $(OPENJDK_TARGET_OS), macosx solaris aix linux), )
+ifeq ($(call isTargetOs, macosx solaris aix linux), true)
   $(eval $(call SetupJdkExecutable, BUILD_JSPAWNHELPER, \
       NAME := jspawnhelper, \
       SRC := $(TOPDIR)/src/$(MODULE)/unix/native/jspawnhelper, \