[Vm-dev] Bug in Interpreter>>primitiveNextPut:

Interpreter >> primitiveNextPut: limit := self fetchInteger: StreamReadLimitIndex ofObject: stream. atIx := (array bitAnd: AtCacheMask) + AtPutBase. (index < limit and: [(atCache at: atIx+AtCacheOop) = array])

so basically, it needs ReadLimit to be > 0. (Which is only true for (Read)WriteStreams if created with on:from:to:).

Changing the first line to limit := self fetchInteger: StreamWriteLimitIndex ofObject: stream.

and the primitive now works. ws := WriteStream on: (String new: 500000). [1 to: 500000 do: [:ix | ws nextPut: $a]] timeToRun

before: 130 after: 33

Inserted a counter after the prim call, for the loop above it was always >= 500000, with fix it's >=1.

Cheers, Henry