Ship jdk7 ct.sym with jdk8?

[Joe Darcy]

On 3/12/2013 1:47 AM, Joel Borggrén-Franck wrote:
> Hi Jon, Martin, all,
>
> On 03/12/2013 12:35 AM, Jonathan Gibbons wrote:
>> On 03/11/2013 04:29 PM, Martin Buchholz wrote:
>>> If you want to build some java software that targets jdk6, the 
>>> natural way
>>> to do it is via -target 6.  But then javac will complain it also wants
>>> -source 6 (that's easy to fix) but also a bootclasspath for jdk6, 
>>> which is
>>> harder for the user to provide.
>>>
>>> One obvious way to make the user's life easier is to ship a ct6.sym,
>>> ct7.sym, ct8.sym,
>>> where each .sym contains the deltas relative to the previous version.
>>>  Then we could have -target 6 default to compiling against ct6.sym, 
>>> while
>>> -target 8 will default to ct8.sym:ct7.sym:ct6.sym
>>>
>>> Perhaps you are already doing this kind of thing to support profiles 
>>> in jdk8?
>>
>> It would be logistically hard to include binary products from earlier 
>> builds
>> in the current build.
>>
>
> Why? It is just a file. If we want to make javac a more robust cross 
> compiler (and I think we should) we should fix the logistics until we 
> can do what we want.

As a rule, the JDK Hg repos do *not* include binary files, just source 
files. Therefore, there could be logistical issues in simply storing the 
old ct.sym files in the repo. We'd ultimately want to use some kind of 
implicit or explicit diff-based compression of the cross-version 
information.

-Joe