--- a/make/autoconf/platform.m4	Wed Mar 28 14:15:41 2018 -0400
+++ b/make/autoconf/platform.m4	Wed Mar 28 21:00:09 2018 +0200
@@ -256,9 +256,12 @@
   OPENJDK_TARGET_CPU_ARCH="$VAR_CPU_ARCH"
   OPENJDK_TARGET_CPU_BITS="$VAR_CPU_BITS"
   OPENJDK_TARGET_CPU_ENDIAN="$VAR_CPU_ENDIAN"
+  OPENJDK_TARGET_OS_UPPERCASE=`$ECHO $OPENJDK_TARGET_OS | $TR 'abcdefghijklmnopqrstuvwxyz' 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'`
+
   AC_SUBST(OPENJDK_TARGET_OS)
   AC_SUBST(OPENJDK_TARGET_OS_TYPE)
   AC_SUBST(OPENJDK_TARGET_OS_ENV)
+  AC_SUBST(OPENJDK_TARGET_OS_UPPERCASE)
   AC_SUBST(OPENJDK_TARGET_CPU)
   AC_SUBST(OPENJDK_TARGET_CPU_ARCH)
   AC_SUBST(OPENJDK_TARGET_CPU_BITS)