I don't know when this started happening but I get this error below copying freetype.dll
and it appears to me that the copy fails because the bin directory has not yet been created.
------
Building OpenJDK for target 'default' in configuration 'windows-x86-normal-server-release'

Creating jdk/jce/unsigned/policy/unlimited/US_export_policy.jar
/usr/bin/cp: cannot create regular file `/cygdrive/c/jdks/jdk9/build/windows-x86-normal-server-release/jdk/bin/freetype.dll': No such file or directory
Copy-java.desktop.gmk:71: recipe for target '/cygdrive/c/jdks/jdk9/build/windows-x86-normal-server-release/jdk/bin/freetype.dll' failed
make[3]: *** [/cygdrive/c/jdks/jdk9/build/windows-x86-normal-server-release/jdk/bin/freetype.dll] Error 1
Main.gmk:138: recipe for target 'java.desktop-copy' failed
make[2]: *** [java.desktop-copy] Error 2


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The fix I'd propose is :-
C:\jdks\jdk9-client\jdk\make\copy>hg diff Copy-java.desktop.gmk
diff -r 07156012ab78 make/copy/Copy-java.desktop.gmk
--- a/make/copy/Copy-java.desktop.gmk Thu Sep 18 17:34:44 2014 +0400
+++ b/make/copy/Copy-java.desktop.gmk Thu Sep 18 12:51:40 2014 -0700
@@ -68,6 +68,7 @@
   endif

   $(FREETYPE_TARGET_LIB): $(FREETYPE_BUNDLE_LIB_PATH)/$(call SHARED_LIBRARY,freetype)
+ $(MKDIR) -p $(JDK_OUTPUTDIR)/bin
        $(CP) $(FREETYPE_BUNDLE_LIB_PATH)/$(call SHARED_LIBRARY,freetype) $@
         ifeq ($(OPENJDK_BUILD_OS), windows)
          $(CHMOD) +rx $@