Unsatisfiability
These errors embody the idea that "something should have been true, but it is not." There are three cases in which this may arise.
Information available
See arrow.meta.plugins.analysis.phases.analysis.solver.checkImplicationOf for the code which produces the errors.
The one constraint name and Boolean formula which could not be satisfied.
A counter-example (also called a model), which is an assignment of values to variableswhich show a specific instance in which the constraint is false.
In the
ffunction above in theUnsatBodyPostepigraph, one such counter-example isx == 0, since in that case0 + 0 > 1is false.By looking at the values of the model for the arguments, we can derive one specific trace for which the function fails.