Program with equality in the body does not terminate

[wanko]

The program

a :- &sum{ x; y } = 4.

does not terminate.

The program

a :- &sum{ x; y } <= 4,&sum{ x;y } >= 4.

terminates instantly.

Comandlines:
echo "a :- &sum{ x; y } = 4." | clingcon -
a :- &sum{ x; y } <= 4,&sum{ x;y } >= 4." | clingcon -

[rkaminsk]

There are some situations in which clingcon unrolls the whole domain of an integer variable during constraint progation. Whether clingcon runs into such a situation on this example depends on how the solver's heuristic selects Boolean variables when branching. I think this is an inherent problem of clingcon's solving algorithm. In practice, it is better to limit the size of domains.