--- a/make/autoconf/spec.gmk.in	Wed Mar 28 14:15:41 2018 -0400
+++ b/make/autoconf/spec.gmk.in	Wed Mar 28 21:00:09 2018 +0200
@@ -65,6 +65,7 @@
 OPENJDK_TARGET_OS:=@OPENJDK_TARGET_OS@
 OPENJDK_TARGET_OS_TYPE:=@OPENJDK_TARGET_OS_TYPE@
 OPENJDK_TARGET_OS_ENV:=@OPENJDK_TARGET_OS_ENV@
+OPENJDK_TARGET_OS_UPPERCASE:=@OPENJDK_TARGET_OS_UPPERCASE@
 
 OPENJDK_TARGET_CPU:=@OPENJDK_TARGET_CPU@
 OPENJDK_TARGET_CPU_ARCH:=@OPENJDK_TARGET_CPU_ARCH@