On 15.01.2010, at 09:18, K. K. Subramaniam wrote:
> 
> Hi,
> 
> I tried running Scratch image with the current VM and found that it bombed 
> with cryptic "a primitive failed" message. Not that I expected to work 
> smoothly but I was surprised about the root cause - many numbered primitives 
> in primitiveTable (unix/src/vm/interp.c) were replaced with primitiveFail 
> instead of being redirected to their respective named primitive. In my case it 
> was primitive 207 (primNetNameResolverStatus).

Hmm, the 3.10 VM used to work fine with Scratch - that must be very recent? Which Scratch image did you try?

> Any reason why new VMs let primitives fail rather redirect them?
> 
> Is backward compability maintained only across the same major version of the 
> VM?

I think so far the VMs pretty much managed to be backwards-compatible even across major versions.

- Bert -