Ground instance computation code appears to be non-deterministic

[viper-admin]

Created by @mschwerhoff on 2017-04-19 13:48

Unit test silver/src/test/scala/DomainInstanceTest.scala includes a check that, for a given Viper file, 259 domain instances should be computed. However, on some runs, 278 instances are computed (and 259 on the others). The instance computation code uses regular Scala sets, which could introduce non-determinism into the computation.

However, it would be good to know why this non-determinism affects the number of computed instances and if this is really desirable.

For now, the check has been disabled.