Question

When I enable the explanation generation option in fixedpoints Z3Py, I am getting a core dump with the following messages.

Error setting ‘DL_GENERATE_EXPLANATIONS’, reason: unknown option.
terminate called after throwing an instance of ‘z3_error’ Aborted
(core dumped)

I am using Z3 4.2 on Ubuntu 12.04, and I get the error for the example given in Z3Py docs in the “Explanations” section.

I am wondering what may be causing this problem.

Answer 1

The options for the fixedpoint engine are going to change for the 4.2.
The documentation is for the last release 4.1.
You can set options to Z3 by setting them directly on the fixedpoint object.
This is similar to how options are administrated on solver objects and tactic objects.
Example,

fp = Fixedpoint()
fp.set(engine='datalog',generate_explanations=True)