build jdk9 from source on mac failed

[wei]

Hi, 
  I tried to build jdk9 from source code on Mac OS 10.10, and got following issue at beginning. The dependent Xcode and JDK have been installed. 
I really appreciate if anyone can share the experience on building jdk9 on Mac. 

Building target 'default (exploded-image)' in configuration 'macosx-x86_64-normal-server-release'
make[2]: *** No rule to make target `java.base-gensrc-hotspot', needed by `java.base-copy-hotspot'.  Stop.
make[2]: *** Waiting for unfinished jobs....
make[3]: BuildHotspot.gmk: No such file or directory
make[3]: *** No rule to make target `BuildHotspot.gmk'.  Stop.
make[2]: *** [hotspot] Error 2
Compiling 8 files for BUILD_TOOLS_LANGTOOLS


Regards!
wei