RFR: JDK-8200083: Bump bootjdk used for JDK 11 at Oracle to JDK 10

[Jonathan Gibbons]

I think one aspect of this discussion that is important and has been 
overlooked is that there is no clear statement (specification?) anywhere 
of the requirements for building OpenJDK. Since forever, the unwritten 
rule has been N-1 [*] and that assumption has become pervasive. And, as 
we have seen in this discussion, there are many consequences to changing 
that assumption.

I think that the decision to change the policy about the boot JDK is too 
important to hide in an edit in an Oracle-only build configuration file.

To be clear, I'm not advocating here for any specific value of N-1, N-2, 
etc,  I'm just saying the policy should be recorded in a more public 
place than make/conf/jib-profiles.js, and should implicitly apply to all 
folk wanting to build OpenJDK in the standard way, and not be just about 
"building JDK 11 at Oracle".

-- Jon

[*] Actually, the rule has been N-1 or N, by virtue of the bootcycle 
builds that used to be more common.



On 4/4/18 1:55 PM, Erik Joelsson wrote:
> Resending with corrected title.
>
>
> On 2018-04-04 13:54, Erik Joelsson wrote:
>> Updating the bootjdk requirement for JDK 11 was controversial. 
>> Instead I propose that for now, we just update the bootjdk used for 
>> building JDK 11 at Oracle to JDK 10 and let compatibility with JDK 9 
>> be a best effort from the parts of the community that wants to 
>> support it.
>>
>> Webrev: http://cr.openjdk.java.net/~erikj/8200083/webrev.02/
>>
>> /Erik
>>
>>
>> On 2018-03-21 14:51, Erik Joelsson wrote:
>>> Now that JDK 10 has been officially released we can update the boot 
>>> jdk requirement for JDK 11. Cross posting this to jdk-dev to raise 
>>> awareness of this rather disruptive change.
>>>
>>> This patch changes the requirement on boot jdk version in configure 
>>> (and updates the configuration that controls what JDK to use as boot 
>>> in Oracle's internal build system).
>>>
>>> Webrev: http://cr.openjdk.java.net/~erikj/8200083/webrev.01/
>>>
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8200083
>>>
>>> /Erik
>>>
>>
>