harmony-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Magnusson, Geir" <geir.magnus...@intel.com>
Subject RE: [classlib] Switching to a 5.0 compiler
Date Wed, 05 Apr 2006 13:10:27 GMT
Sorry about posting from outlook..

> -----Original Message-----
> From: Tim Ellison [mailto:t.p.ellison@gmail.com] 
> Sent: Wednesday, April 05, 2006 7:52 AM
> To: harmony-dev@incubator.apache.org
> Subject: Re: [classlib] Switching to a 5.0 compiler
> 
> Geir Magnusson Jr wrote:
> > Tim Ellison wrote:
> >> A while ago we agreed to switch to a class library 
> compilation story
> >> that would allow us to use 1.5 Java syntax on a 
> 1.4-compatible VM (i.e.
> >> using syntax that is erased by the compiler).
> >>
> >> Here's where I'm at...
> >>
> >>
> >> Using the Sun compiler:
> >>
> >> Specifying source=1.5 and target=1.4 (understandably) fails as an
> >> invalid option set, but there is an undocumented and 
> unmaintained option
> >> that, AIUI, was introduced during the syntax transition to full 1.5
> >> support.  On Sun-based compilers we can specify source=1.5 
> target=jsr14
> >> and get some support for erased 1.5 syntax.
> > 
> > Ok
> > 
> > 
> >>
> >> Using the Eclipse compiler:
> >>
> >> In the Eclipse JDT UI you *can* specify source=5.0 target=1.4 and I
> >> successfully ran code written using generics on a 1.4 VM.  
> However, the
> >> Eclipse batch compiler does not allow this source=5.0 target=1.4
> >> combination; and when I asked why the answer was that the 
> UI usage is
> >> wrong and will be fixed to prevent that combination.
> > 
> > LOL!  How about suggesting that users find it useful right now?
> 
> My understanding is that there is a spec compliance issue, hence...

Maybe you could tell them about "source=1.5 target=jsr14" given that's
the behavior of the Sun's.

What spec, btw?


> 
> >> Unless we void the warranty on the compiler by making 
> non-API calls into
> >> their code we cannot therefore use the Eclipse to do back-level
> >> compilations.
> > 
> > Warranty?  From Eclipse?  <chuckle>
> 
> (that was a joke BTW, I guess it needed a winky)
> 
> my point is that we could hack the Eclipse batch compiler to 
> make it do
> something it is not meant to do (source=1.5 target=1.4).  If we get
> burnt then we'll have nobody to complain to ;-)

Right, and I think there's little risk as it isn't a long term
solution...

[SNIP]

> > 
> >> Comments?
> > 
> > Thanks for doing this.
> > 
> > It seems like we have two options - Sun and Eclipse, and because the
> > eclipse compiler is CDDL, and can be integrated into our 
> build system,
> > we seem to be safe.
> 
> As it stands we have no option to use the Eclipse batch compiler
> (without tweaking it and therefore I assume bringing a 
> modified JAR into
> our SVN for people to use etc. -- yuk!)

Can't we just write a little wrapper to call into it?

> 
> > Sun isn't going to change, I'd bet, and in the event 
> Eclipse does, we
> > simply fork it. :)
> > 
> > This really is a temporary situation.  Maybe the thing to do is
> > 
> > 1) get as much non-1.5 things done as possible this week or 
> two (yes, I
> > know it's "Java 5" now, but  calling it 1.5 is a good 
> parallel to 1.4)
> 
> We should do this anyway.
> 
> > 2) do a snapshot and also make a branch, for discussion sake call it
> > branch_1.4, which is unsupported and not an official 
> objective of the
> > project
> 
> Hmm, you mean branch so that VMs can implement the VMI to that level
> before moving on to 1.5?
> 
> > 3) In head, get going w/ erasable 5 stuff under the assumption that
> > we'll be able to use Sun and Eclipse, for a while anyway.
> 
> ... and use a source=1.5 target=1.5 compiler setting, and run 
> it on...a
> new IBM VME?  Is that what you were thinking?
> 
> > 4) If anyone feels sufficiently motivated, they can add to 
> branch_1.4 if
> > we get more good code that we'd want to make available to 
> the other 1.4
> > VMs out there, but again, it's not something we as a project would
> > commit to do - people could work on it as they see fit...
> 
> I see more people chomping at the bit to use 5.0 syntax rather than
> continue on 1.4 -- we are just waiting for the VMs to catch up ;-)

Right - so if no one worked on it, no harm done.  But if someone out
there w/ a 1.4 VM wanted to test what we're doing in harmony, they still
could...

Geir

> 
> Regards,
> Tim
> 
> -- 
> 
> Tim Ellison (t.p.ellison@gmail.com)
> IBM Java technology centre, UK.
> 
> ---------------------------------------------------------------------
> Terms of use : http://incubator.apache.org/harmony/mailing.html
> To unsubscribe, e-mail: harmony-dev-unsubscribe@incubator.apache.org
> For additional commands, e-mail: harmony-dev-help@incubator.apache.org
> 

---------------------------------------------------------------------
Terms of use : http://incubator.apache.org/harmony/mailing.html
To unsubscribe, e-mail: harmony-dev-unsubscribe@incubator.apache.org
For additional commands, e-mail: harmony-dev-help@incubator.apache.org


Mime
View raw message