JDK8 no longer required to develop Graal

[Doug Simon]

> On 15 Aug 2018, at 18:07, Jackson Davis <jackson at jcdav.is> wrote:
> 
> 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.

Good to hear - that was the point ;-)

> 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

@Christian, Svata: Do you know what is necessary to update C1Visualizer to a more recent NetBeans platform that supports JDK 9+?

> 
> 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.

I think the best path forward is producing a new C1Visualizer as mentioned above.

> 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?

We will look into it.

-Doug

> 
> 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/c9f873aa979b2a724e7e213fd1e0d4ce7131b87f
> [2] https://github.com/oracle/graal/commit/a4070ec3d1b16d49f42694b3f0a46a39010b445c
>