hg: valhalla/valhalla: [lworld] Withdraw support for the __Flattenable and __NotFlattened field modifiers.

[Karen Kinnear]

Srikanth, Tobias,

Yes please to push this patch to move these modifiers under the experimental flag. this is a much better approach.

LW1 is a really tight deadline right now and we don’t want to cause extra work.
My apologies for missing the implications.

thank you both,
Karen

> On Jun 26, 2018, at 7:23 AM, Srikanth <srikanth.adayapalam at oracle.com> wrote:
> 
> 
> The attached patch would cause the flattenability modifiers to be accepted with their erstwhile syntax and semantics when javac is invoked with -XDallowFlattenabilityModifiers
> 
> I'll wait to hear from Karen and push/discard accordingly.
> 
> (I am likely away Thursday/Friday, I will be available on Wednesday. Posting a patch here, so if it is required in my absence it can be availed. It passes all langtools tests)
> 
> Thanks!
> Srikanth
> 
> On Tuesday 26 June 2018 03:38 PM, Srikanth wrote:
>> 
>> 
>> On Tuesday 26 June 2018 03:32 PM, Tobias Hartmann wrote:
>>> Hi Srikanth,
>>> 
>>> On 26.06.2018 11:37, Srikanth wrote:
>>>> I did have an express go from Karen to "nuke" these source level modifiers before proceeding. But in
>>>> light of what you say, I'll take a look and see what is involved in pushing these under an option
>>>> instead.
>>> Thanks for looking into it but we should probably wait for Karen to comment on that. I guess I
>>> missed the discussion/decision of fully removing these modifiers (I thought we just don't want to
>>> support them for LW1).
>> 
>> Sounds good to me. I'll keep a patch ready in any case and after hearing from Karen decide to push or discard.
>> 
>> I believe the consensus in the VM is to move away fromACC_FLATTENABLE on fields to using the ValueTypes attribute.
>> 
>> Your concern below about the code rot is valid.
>> 
>> Srikanth
>>> 
>>>> Even with that many of the tests would need "massaging" but I guess it won't shut you out from
>>>> retaining the support for non-flattened value type fields.
>>> Yes, I'm fine with modifying the tests, I'm just concerned that without testing the implementation
>>> of non-flattenable fields in the JVM, the code will start to rot very soon.
>>> 
>>> Thanks,
>>> Tobias
>> 
> 
> <flat.txt>