JDK8 no longer required to develop Graal

[Jackson Davis]

First off, a belated thanks for this - I've been wanting to get back into
playing around with Graal, and this makes things much easier.

As a related note though, the story for using the graph visualization tools
is currently a bit of a mess. In particular, c1vis seems to be based off an
earlier version of Netbeans that doesn't work with JDKs >= 9, I see an
error message similar to this in the log:
https://stackoverflow.com/questions/46170762/netbeans-8-1-ide-exits-unexpectedly-on-ubuntu-17-04

But then if I supply a normal (non-JVMCI) jdk8 build as a java home to use,
mx rejects it (even with JVMCI_VERSION_CHECK=ignore), even though JVMCI
shouldn't be necessary for just running this. The workaround seems to be
just manually downloading c1vis and running it pointing at a jdk8, but it
would be nice to be able to do this through the mx command.

IGV doesn't seem to have this issue, but since the most easily-accessible
javafx-compatible builds are jdk8-based (eg sudo apt-get install openjfx),
you still need to jump through some hoops of having the right jdk to get it
to work. Ideally the JVMCI requirement could be avoided for these?

-Jackson


On Mon, Aug 13, 2018 at 5:23 AM, Doug Simon <doug.simon at oracle.com> wrote:

> Developing Graal has always required a JDK8 to be present in either
> JAVA_HOME or EXTRA_JAVA_HOMES. Please see http://mail.openjdk.java.net/
> pipermail/graal-dev/2018-June/005413.html for background on this.
>
> I've recently pushed changes to mx[1] and Graal[2] that removes this
> requirement. That is, you should now be able to develop Graal with only a
> JDK11 in JAVA_HOME. I have updated https://github.com/oracle/
> graal/blob/master/compiler/README.md#building-graal to reflect this.
>
> If you run into any problems developing Graal with only a JDK 11, please
> open an issue at https://github.com/oracle/graal/issues or send a message
> to graal-dev at openjdk.java.net.
>
> -Doug
>
> [1] https://github.com/graalvm/mx/commit/c9f873aa979b2a724e7e213fd1e0d4
> ce7131b87f
> [2] https://github.com/oracle/graal/commit/a4070ec3d1b16d49f42694b3f0a46a
> 39010b445c