Continuations interact badly with .return

[arnsholt]

I'm trying to implement non-deterministic search (backtracking), for a tentative continuation-passing Prolog on Parrot. Fiddling with this, I've stumbled upon what seems like a strange issue with continuations.

The code is adapted from the Scheme in Paul Graham's On Lisp.

test.pir contains my original test code. As is clear from the output, choose() gets the right value, but the calling code somehow always gets the first value.

In an attempt to condense the code a bit I wrote bug.pir, which exhibits some interesting behaviour. The return value keeps the value from the last return. Possibly the continuation resumes from a slightly wrong position?

[arnsholt]

Original code

[arnsholt]

(Slightly) condensed code.

[bacek]

Issue was resolved in pcc_hackatron branch. Test added in r45123. Resolving ticket.