Error when matching rabbits: by_subplan: planner_multi_avail_during returned -1

[jameshcorbett]

With this JGF and the jobspec below, I get the following error even though the match succeeds:

version: 9999
resources:
  - type: slot
    count: 2
    label: default
    with:
    - type: ssd
      count: 1
    - type: node
      exclusive: true
      count: 1
      with:
      - type: slot
        label: task
        count: 1
        with:
        - type: core
          count: 1
# a comment
attributes:
  system:
    duration: 3600
tasks:
  - command: [ "app" ]
    slot: task
    count:
      per_slot: 1

ERROR: by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
Invalid argument.
by_subplan: planner_multi_avail_during returned -1.
[snip -- continues for many many lines]