[11u] Desupport building with Java 10?

[Severin Gehwolf]

On Thu, 2022-02-17 at 08:04 +0000, Lindenmaier, Goetz wrote:
> Hi,
> 
> OpenJDK has the policy that each jdk should be able to
> be bootstrapped with the previous Java version.
> See also DEFAULT_ACCEPTABLE_BOOT_VERSIONS [1].
> This makes sense for new Java versions but not for
> updates of LTSes.

Why not?

>  For jdk11u, using a Java 10 jdk
> for bootstrapping even is a security issue as there
> is no maintained jdk10.

I'm not sure I'm bying the security argument for the bootstrap process.

> On the other side we had to fix a few changes in
> the past to work with Java 10.  We should avoid this
> effort.

In the past getting this to work wasn't a lot of effort. Do you have
some data were it is *indeed* a lot of effort?

> I propose to give up supporting Java 10 in the build
> in 11.0.16 and to change DEFAULT_ACCEPTABLE_BOOT_VERSIONS
> accordingly.
> 
> If there are no objections I'll do the corresponding
> change for 11.0.16.

This isn't a good idea. It breaks the bootstrap chain. Unless there are
good cases where the "cost of maintaining JDK 10 bootstrap support" >>>
"benefit of being able to bootstrap the latest JDK 11", I'm against it.

Thanks,
Severin