[etoys-dev] Image-segments and closures

[Bert Freudenberg]

That's something we will have to look out for, too ...

- Bert -

Begin forwarded message:
> 
> From: Andreas Raab <andreas.raab at gmx.de>
> Date: 16. März 2010 00:05:42 MEZ
> To: The general-purpose Squeak developers list <squeak-dev at lists.squeakfoundation.org>
> Cc: Squeak Virtual Machine Development Discussion <vm-dev at lists.squeakfoundation.org>
> Subject: [Vm-dev] Re: Some notes about SqueakMap dead in trunk images...
> Reply-To: Squeak Virtual Machine Development Discussion <vm-dev at lists.squeakfoundation.org>
> 
> On 3/15/2010 1:26 PM, Göran Krampe wrote:
>> But so far I am unclear as to why this is so. I have now tested LOTS of
>> trunk images backwards and it seems to be broken all the way down to
>> 7179! Funny thing is - my 3.10.1-7175 image works fine.
>> 
>> And there may be a hint here: The 7175 image can be opened by an old
>> 3-9-8 VM. But the later 7179 images can NOT be opened due to some kind
>> of image format change.
> 
> Bingo. The issue is that the image format changed for closures and there's been a bug in the image segment loading code that makes the primitive fail in cases where the image format is older, but compatible. I've posted a fix for that in VMMaker but I really think SM should stop using image segments for data exchange. Image segments are not a reliable long-term interchange format in an evolving system.
> 
> Obviously, this fix requires new VMs.
> 
> Cheers,
>  - Andreas