- update to 4.11.2:
* add error handling to fromString method in JavaScript
* fix regression in default parameters for CDCL, thanks to Nuno Lopes
* fix model evaluation bugs for as-array nested under functions (data-type constructors)
* add rewrite simplifications for datatypes with a single constructor
* add "Global Guidance" capability to SPACER, thanks to Arie Gurfinkel and Hari Gorvind.
* change proof logging format for the new core to use SMTLIB commands.
The format was so far an extension of DRAT used by SAT solvers, but not well compatible
with SMT format that is extensible. The resulting format is a mild extension of SMTLIB with
three extra commands assume, learn, del. They track input clauses, generated clauses and deleted clauses.
They are optionally augmented by proof hints. Two proof hints are used in the current version: "rup" and "farkas".
"rup" is used whent the generated clause can be justified by reverse unit propagation. "farkas" is used when
the clause can be justified by a combination of Farkas cutting planes. There is a built-in proof checker for the
format. Quantifier instantiations are also tracked as proof hints.
Other proof hints are to be added as the feature set is tested and developed. The fallback, buit-in,
self-checker uses z3 to check that the generated clause is a consequence. Note that this is generally
insufficient as generated clauses are in principle required to only be satisfiability preserving.
Proof checking and tranformation operations is overall open ended.
The log for the first commit introducing this change contains further information on the format.
* fix to re-entrancy bug in user propagator (thanks to Clemens Eisenhofer).
* handle _toExpr for quantified formulas in JS bindings