--- old/make/autoconf/buildjdk-spec.gmk.in	2017-12-14 12:54:47.727205725 +0100
+++ new/make/autoconf/buildjdk-spec.gmk.in	2017-12-14 12:54:47.443195776 +0100
@@ -55,6 +55,7 @@
 OPENJDK_TARGET_CPU_BITS := @OPENJDK_BUILD_CPU_BITS@
 OPENJDK_TARGET_CPU_ENDIAN := @OPENJDK_BUILD_CPU_ENDIAN@
 OPENJDK_TARGET_CPU_LEGACY := @OPENJDK_BUILD_CPU_LEGACY@
+OPENJDK_TARGET_OS_INCLUDE_SUBDIR := @OPENJDK_BUILD_OS_INCLUDE_SUBDIR@
 
 HOTSPOT_TARGET_OS := @HOTSPOT_BUILD_OS@
 HOTSPOT_TARGET_OS_TYPE := @HOTSPOT_BUILD_OS_TYPE@