RFR(XS): 8033951: nasgen needs the newly build nasgen and nashorn classes in the bootclasspath

[Volker Simonis]

Hi,

could you please review the following tiny change which fixes an issue
in the nashorn build:

https://bugs.openjdk.java.net/browse/JDK-8033951
http://cr.openjdk.java.net/~simonis/webrevs/8033951/

This fix is for jdk9 but I shink it should be down-ported into 8udev as well.

Here some background information:

During the nashorn build, the nasgen tool is called as follows:

<boot_jdk>/bin/java \
  -Xms64M -Xmx1100M \
  -XX:PermSize=32m \
  -XX:MaxPermSize=160m \
  -XX:ThreadStackSize=1536 \
  -cp "<build_dir>/nashorn/nasgen_classes:<build_dir>/nashorn/nashorn_classes"\
  jdk.nashorn.internal.tools.nasgen.Main \
  <build_dir>/nashorn/classes jdk.nashorn.internal.objects
<build_dir>/nashorn/classes

The problem is that the call puts the newly created nashorn and nasgen
class (which also include the required asm class) into the class path.
This will lead to problems, if the boot jdk contains different version
of some of these classes.

Until now, this problem was seldom, because jdk7 doens't contain any
of these classes, so no conflicts could occur. But building a new
version of jdk8/jdk9 with an older jdk8 boot-jdk may lead to build
errors like this:

/share/software/Java/jdk1.8.0_ea_b70/bin/java -Xms64M -Xmx1100M
-XX:ThreadStackSize=1536 \
            -Xbootclasspath/p:"/tmp/jdk9-client-opt/nashorn/nasgen_classes"
-cp "/tmp/jdk9-client-opt/nashorn/nashorn_classes" \
            jdk.nashorn.internal.tools.nasgen.Main
/tmp/jdk9-client-opt/nashorn/classes jdk.nashorn.internal.objects
/tmp/jdk9-client-opt/nashorn/classes
Exception in thread "main" java.lang.NoClassDefFoundError:
jdk/nashorn/internal/objects/annotations/ScriptClass
        at jdk.nashorn.internal.tools.nasgen.ScriptClassInfo.<clinit>(ScriptClassInfo.java:52)
        at jdk.nashorn.internal.tools.nasgen.ScriptClassInfoCollector.visitAnnotation(ScriptClassInfoCollector.java:82)
        at jdk.internal.org.objectweb.asm.ClassReader.accept(ClassReader.java:670)
        at jdk.internal.org.objectweb.asm.ClassReader.accept(ClassReader.java:535)
        at jdk.nashorn.internal.tools.nasgen.ClassGenerator.getScriptClassInfo(ClassGenerator.java:370)
        at jdk.nashorn.internal.tools.nasgen.ClassGenerator.getScriptClassInfo(ClassGenerator.java:365)
        at jdk.nashorn.internal.tools.nasgen.Main.process(Main.java:104)
        at jdk.nashorn.internal.tools.nasgen.Main.processAll(Main.java:88)
        at jdk.nashorn.internal.tools.nasgen.Main.main(Main.java:62)
make[1]: *** [/tmp/jdk9-client-opt/nashorn/classes/_the.nasgen.run] Error 1
make[1]: Leaving directory
`/net/usr.work/d046063/OpenJDK/jdk9-client/nashorn/make'

Also see the message "Compilation failure due to mismatching internal
classes in the boot JDK" at
http://mail.openjdk.java.net/pipermail/nashorn-dev/2014-January/002687.html

The fix for this is easy - just put the required classes in the boot
class path instead just in the class path.

Regards,
Volker