(apologies for the duplicate reply; someone needs to sort out their threading for the benefit of the community ;) )
On Thu, Sep 22, 2011 at 2:36 AM, Marcus Denker <[email protected]>wrote: > Hi, > > There are two changesets waiting for integrating in 1.4 that have serious > consequences: > > - Ephemerons. The VM level changes are in the Cog VMs build on Jenkins, but > have not > been integrated in the VMMaker codebase. > > http://code.google.com/p/pharo/issues/detail?id=4265 I would *really* like to back out these changes. The Ephemeron implementation is very much a prototype, requiring a hack to determine whether an object is an ephemeron (the presence of a marker class in the first inst var) that I'm not at all happy with. There is a neater implementation available via using an unused instSpec which IMO has significant advantages (much simpler & faster, instSpec is valid at all times, including during compaction, less overhead, doesn't require a marker class), and is the route I'm taking with the new GC/object-representation I'm working on now. Note that other than determining whether an object is an ephemeron (instSpec/format vs inst var test) the rest of Igor's code remains the same. I'd like to avoid too much VM forking. Would you all consider putting these changes on hold for now? If so, I'll make the effort to produce prototype changes (in the area of ClassBuilder and class definition; no VM code necessary as yet) to allow defining Ephemerons via the int spec route by next week at the latest. > > > - Finalization code checks for #hasNewFinalization > This is true in the current VMs build in Jenkins, but in older VMs this is > not in. > > http://code.google.com/p/pharo/issues/detail?id=4483 > > There are two options: > > a) integrate in > b) not integrate it > > a) means that the image runs on older VMs, too. > b) means we accept that we can never improve anything for real. > > There will be more changes coming... e.g. imagine we have a Vector Graphics > Canvas > as some point next year... what will we do? use it or not use it to stay > compatible? > > Marcus > > > -- > Marcus Denker -- http://marcusdenker.de > > > -- best, Eliot
