diff -r 0c4c976612d3 -r cb1203f48728 common/autoconf/spec.gmk.in
--- a/common/autoconf/spec.gmk.in	Wed Apr 18 12:37:18 2018 -0700
+++ b/common/autoconf/spec.gmk.in	Tue Apr 17 09:33:36 2018 -0700
@@ -101,6 +101,7 @@
 # When not cross-compiling, it is the same as the target.
 OPENJDK_BUILD_OS:=@OPENJDK_BUILD_OS@
 OPENJDK_BUILD_OS_API:=@OPENJDK_BUILD_OS_API@
+OPENJDK_BUILD_OS_ENV:=@OPENJDK_BUILD_OS_ENV@
 
 OPENJDK_BUILD_CPU:=@OPENJDK_BUILD_CPU@
 OPENJDK_BUILD_CPU_ARCH:=@OPENJDK_BUILD_CPU_ARCH@