/usr/bin/java -Xmx8000000000 -Xss4m -jar ./plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -data @noDefault -ultimatedata ./data -tc ../../../trunk/examples/toolchains/AutomizerC.xml --traceabstraction.trace.refinement.strategy FIXED_PREFERENCES --traceabstraction.compute.interpolants.along.a.counterexample Craig_NestedInterpolation --traceabstraction.smt.solver Internal_SMTInterpol --traceabstraction.compute.trace.for.counterexample.result false --traceabstraction.use.minimal.unsat.core.enumeration true --traceabstraction.additional.smt.options interpolation-heuristic=FIRST --traceabstraction.additional.smt.options log-additional-information=true -s ../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf -i ../../../trunk/examples/svcomp/recursive/Ackermann02.c -------------------------------------------------------------------------------- This is Ultimate 0.1.25-177f698 [2020-08-21 14:53:09,973 INFO L177 SettingsManager]: Resetting all preferences to default values... [2020-08-21 14:53:09,975 INFO L181 SettingsManager]: Resetting UltimateCore preferences to default values [2020-08-21 14:53:10,007 INFO L184 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... 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[2020-08-21 14:53:10,033 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2020-08-21 14:53:10,035 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2020-08-21 14:53:10,038 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2020-08-21 14:53:10,039 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2020-08-21 14:53:10,040 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2020-08-21 14:53:10,042 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2020-08-21 14:53:10,043 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2020-08-21 14:53:10,051 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2020-08-21 14:53:10,053 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2020-08-21 14:53:10,054 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2020-08-21 14:53:10,055 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2020-08-21 14:53:10,056 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2020-08-21 14:53:10,068 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... 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[2020-08-21 14:53:10,083 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2020-08-21 14:53:10,084 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2020-08-21 14:53:10,085 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2020-08-21 14:53:10,085 INFO L101 SettingsManager]: Beginning loading settings from /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf [2020-08-21 14:53:10,128 INFO L113 SettingsManager]: Loading preferences was successful [2020-08-21 14:53:10,129 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2020-08-21 14:53:10,131 INFO L136 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2020-08-21 14:53:10,132 INFO L138 SettingsManager]: * Create parallel compositions if possible=false [2020-08-21 14:53:10,132 INFO L138 SettingsManager]: * Use SBE=true [2020-08-21 14:53:10,132 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2020-08-21 14:53:10,132 INFO L138 SettingsManager]: * sizeof long=4 [2020-08-21 14:53:10,133 INFO L138 SettingsManager]: * Overapproximate operations on floating types=true [2020-08-21 14:53:10,133 INFO L138 SettingsManager]: * sizeof POINTER=4 [2020-08-21 14:53:10,133 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2020-08-21 14:53:10,134 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2020-08-21 14:53:10,134 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2020-08-21 14:53:10,134 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2020-08-21 14:53:10,135 INFO L138 SettingsManager]: * sizeof long double=12 [2020-08-21 14:53:10,136 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2020-08-21 14:53:10,136 INFO L138 SettingsManager]: * Use constant arrays=true [2020-08-21 14:53:10,136 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2020-08-21 14:53:10,136 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2020-08-21 14:53:10,136 INFO L138 SettingsManager]: * Size of a code block=SequenceOfStatements [2020-08-21 14:53:10,137 INFO L138 SettingsManager]: * To the following directory=./dump/ [2020-08-21 14:53:10,137 INFO L138 SettingsManager]: * SMT solver=External_DefaultMode [2020-08-21 14:53:10,137 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-08-21 14:53:10,137 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2020-08-21 14:53:10,138 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2020-08-21 14:53:10,138 INFO L138 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2020-08-21 14:53:10,138 INFO L138 SettingsManager]: * Trace refinement strategy=CAMEL [2020-08-21 14:53:10,138 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2020-08-21 14:53:10,138 INFO L138 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2020-08-21 14:53:10,138 INFO L138 SettingsManager]: * Trace refinement exception blacklist=NONE [2020-08-21 14:53:10,139 INFO L138 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Trace refinement strategy -> FIXED_PREFERENCES Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Compute Interpolants along a Counterexample -> Craig_NestedInterpolation Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: SMT solver -> Internal_SMTInterpol Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Compute trace for counterexample result -> false Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Use minimal unsat core enumeration -> true Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Additional SMT options -> interpolation-heuristic=FIRST;log-additional-information=true; Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Additional SMT options -> interpolation-heuristic=FIRST;log-additional-information=true; [2020-08-21 14:53:10,417 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2020-08-21 14:53:10,428 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2020-08-21 14:53:10,438 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2020-08-21 14:53:10,440 INFO L271 PluginConnector]: Initializing CDTParser... [2020-08-21 14:53:10,440 INFO L275 PluginConnector]: CDTParser initialized [2020-08-21 14:53:10,441 INFO L429 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/recursive/Ackermann02.c [2020-08-21 14:53:10,501 INFO L220 CDTParser]: Created temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/0a10cc21d/4163a1dc307f49b38395f11f3211d409/FLAGce633500f [2020-08-21 14:53:10,893 INFO L306 CDTParser]: Found 1 translation units. [2020-08-21 14:53:10,894 INFO L160 CDTParser]: Scanning /storage/repos/ultimate-2/trunk/examples/svcomp/recursive/Ackermann02.c [2020-08-21 14:53:10,899 INFO L349 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/0a10cc21d/4163a1dc307f49b38395f11f3211d409/FLAGce633500f [2020-08-21 14:53:11,281 INFO L357 CDTParser]: Successfully deleted /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/0a10cc21d/4163a1dc307f49b38395f11f3211d409 [2020-08-21 14:53:11,292 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2020-08-21 14:53:11,293 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2020-08-21 14:53:11,295 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2020-08-21 14:53:11,295 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2020-08-21 14:53:11,298 INFO L275 PluginConnector]: CACSL2BoogieTranslator initialized [2020-08-21 14:53:11,299 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,302 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@78532141 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11, skipping insertion in model container [2020-08-21 14:53:11,303 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,310 INFO L145 MainTranslator]: Starting translation in SV-COMP mode [2020-08-21 14:53:11,328 INFO L178 MainTranslator]: Built tables and reachable declarations [2020-08-21 14:53:11,514 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-08-21 14:53:11,521 INFO L203 MainTranslator]: Completed pre-run [2020-08-21 14:53:11,543 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-08-21 14:53:11,559 INFO L208 MainTranslator]: Completed translation [2020-08-21 14:53:11,561 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11 WrapperNode [2020-08-21 14:53:11,561 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2020-08-21 14:53:11,562 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2020-08-21 14:53:11,562 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2020-08-21 14:53:11,562 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2020-08-21 14:53:11,577 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,579 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,698 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,698 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,707 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,710 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,712 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (1/1) ... [2020-08-21 14:53:11,714 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2020-08-21 14:53:11,715 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2020-08-21 14:53:11,715 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2020-08-21 14:53:11,715 INFO L275 PluginConnector]: RCFGBuilder initialized [2020-08-21 14:53:11,716 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (1/1) ... No working directory specified, using /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-08-21 14:53:11,790 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2020-08-21 14:53:11,790 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2020-08-21 14:53:11,791 INFO L138 BoogieDeclarations]: Found implementation of procedure ackermann [2020-08-21 14:53:11,791 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2020-08-21 14:53:11,791 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_error [2020-08-21 14:53:11,791 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_int [2020-08-21 14:53:11,791 INFO L130 BoogieDeclarations]: Found specification of procedure ackermann [2020-08-21 14:53:11,791 INFO L130 BoogieDeclarations]: Found specification of procedure main [2020-08-21 14:53:11,792 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2020-08-21 14:53:11,792 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2020-08-21 14:53:12,126 INFO L290 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2020-08-21 14:53:12,126 INFO L295 CfgBuilder]: Removed 0 assume(true) statements. [2020-08-21 14:53:12,130 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 21.08 02:53:12 BoogieIcfgContainer [2020-08-21 14:53:12,130 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2020-08-21 14:53:12,132 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2020-08-21 14:53:12,132 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2020-08-21 14:53:12,135 INFO L275 PluginConnector]: TraceAbstraction initialized [2020-08-21 14:53:12,136 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 21.08 02:53:11" (1/3) ... [2020-08-21 14:53:12,136 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@42685b84 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 21.08 02:53:12, skipping insertion in model container [2020-08-21 14:53:12,137 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.08 02:53:11" (2/3) ... [2020-08-21 14:53:12,137 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@42685b84 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 21.08 02:53:12, skipping insertion in model container [2020-08-21 14:53:12,137 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 21.08 02:53:12" (3/3) ... [2020-08-21 14:53:12,139 INFO L109 eAbstractionObserver]: Analyzing ICFG Ackermann02.c [2020-08-21 14:53:12,150 INFO L157 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:Craig_NestedInterpolation Determinization: PREDICATE_ABSTRACTION [2020-08-21 14:53:12,157 INFO L169 ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations. [2020-08-21 14:53:12,171 INFO L251 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2020-08-21 14:53:12,196 INFO L375 AbstractCegarLoop]: Interprodecural is true [2020-08-21 14:53:12,196 INFO L376 AbstractCegarLoop]: Hoare is true [2020-08-21 14:53:12,196 INFO L377 AbstractCegarLoop]: Compute interpolants for Craig_NestedInterpolation [2020-08-21 14:53:12,196 INFO L378 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2020-08-21 14:53:12,197 INFO L379 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2020-08-21 14:53:12,197 INFO L380 AbstractCegarLoop]: Difference is false [2020-08-21 14:53:12,197 INFO L381 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2020-08-21 14:53:12,197 INFO L385 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2020-08-21 14:53:12,216 INFO L276 IsEmpty]: Start isEmpty. Operand 27 states. [2020-08-21 14:53:12,224 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 16 [2020-08-21 14:53:12,224 INFO L414 BasicCegarLoop]: Found error trace [2020-08-21 14:53:12,225 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-08-21 14:53:12,226 INFO L427 AbstractCegarLoop]: === Iteration 1 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-21 14:53:12,232 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-21 14:53:12,232 INFO L82 PathProgramCache]: Analyzing trace with hash -1796234678, now seen corresponding path program 1 times [2020-08-21 14:53:12,239 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-21 14:53:12,240 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [355380464] [2020-08-21 14:53:12,240 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-21 14:53:12,337 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:12,390 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-21 14:53:12,391 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:12,395 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 7 [2020-08-21 14:53:12,399 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:12,441 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-08-21 14:53:12,442 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [355380464] [2020-08-21 14:53:12,448 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-08-21 14:53:12,449 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2020-08-21 14:53:12,450 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [725721772] [2020-08-21 14:53:12,454 INFO L459 AbstractCegarLoop]: Interpolant automaton has 5 states [2020-08-21 14:53:12,455 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-21 14:53:12,466 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2020-08-21 14:53:12,467 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2020-08-21 14:53:12,469 INFO L87 Difference]: Start difference. First operand 27 states. Second operand 5 states. [2020-08-21 14:53:12,599 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-21 14:53:12,599 INFO L93 Difference]: Finished difference Result 55 states and 77 transitions. [2020-08-21 14:53:12,600 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2020-08-21 14:53:12,601 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 15 [2020-08-21 14:53:12,602 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-21 14:53:12,613 INFO L225 Difference]: With dead ends: 55 [2020-08-21 14:53:12,613 INFO L226 Difference]: Without dead ends: 28 [2020-08-21 14:53:12,617 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 9 GetRequests, 5 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2020-08-21 14:53:12,636 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 28 states. [2020-08-21 14:53:12,662 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 28 to 28. [2020-08-21 14:53:12,663 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 28 states. [2020-08-21 14:53:12,665 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 28 states to 28 states and 35 transitions. [2020-08-21 14:53:12,667 INFO L78 Accepts]: Start accepts. Automaton has 28 states and 35 transitions. Word has length 15 [2020-08-21 14:53:12,667 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-21 14:53:12,668 INFO L479 AbstractCegarLoop]: Abstraction has 28 states and 35 transitions. [2020-08-21 14:53:12,668 INFO L480 AbstractCegarLoop]: Interpolant automaton has 5 states. [2020-08-21 14:53:12,668 INFO L276 IsEmpty]: Start isEmpty. Operand 28 states and 35 transitions. [2020-08-21 14:53:12,670 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 23 [2020-08-21 14:53:12,671 INFO L414 BasicCegarLoop]: Found error trace [2020-08-21 14:53:12,671 INFO L422 BasicCegarLoop]: trace histogram [2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-08-21 14:53:12,671 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2020-08-21 14:53:12,671 INFO L427 AbstractCegarLoop]: === Iteration 2 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-21 14:53:12,672 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-21 14:53:12,672 INFO L82 PathProgramCache]: Analyzing trace with hash -895156504, now seen corresponding path program 1 times [2020-08-21 14:53:12,672 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-21 14:53:12,673 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [338055898] [2020-08-21 14:53:12,673 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-21 14:53:12,694 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:12,727 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-21 14:53:12,728 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:12,731 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 7 [2020-08-21 14:53:12,739 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:12,773 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 3 [2020-08-21 14:53:12,777 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:12,797 INFO L134 CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 2 refuted. 0 times theorem prover too weak. 2 trivial. 0 not checked. [2020-08-21 14:53:12,798 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [338055898] [2020-08-21 14:53:12,798 INFO L220 FreeRefinementEngine]: Constructing automaton from 0 perfect and 1 imperfect interpolant sequences. [2020-08-21 14:53:12,799 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [6] total 6 [2020-08-21 14:53:12,799 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1585386677] [2020-08-21 14:53:12,801 INFO L459 AbstractCegarLoop]: Interpolant automaton has 6 states [2020-08-21 14:53:12,801 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-21 14:53:12,801 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 6 interpolants. [2020-08-21 14:53:12,802 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=10, Invalid=20, Unknown=0, NotChecked=0, Total=30 [2020-08-21 14:53:12,802 INFO L87 Difference]: Start difference. First operand 28 states and 35 transitions. Second operand 6 states. [2020-08-21 14:53:13,066 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-21 14:53:13,066 INFO L93 Difference]: Finished difference Result 43 states and 60 transitions. [2020-08-21 14:53:13,068 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 7 states. [2020-08-21 14:53:13,068 INFO L78 Accepts]: Start accepts. Automaton has 6 states. Word has length 22 [2020-08-21 14:53:13,069 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-21 14:53:13,071 INFO L225 Difference]: With dead ends: 43 [2020-08-21 14:53:13,072 INFO L226 Difference]: Without dead ends: 39 [2020-08-21 14:53:13,074 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 13 GetRequests, 7 SyntacticMatches, 0 SemanticMatches, 6 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 1 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=20, Invalid=36, Unknown=0, NotChecked=0, Total=56 [2020-08-21 14:53:13,075 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 39 states. [2020-08-21 14:53:13,095 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 39 to 39. [2020-08-21 14:53:13,096 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 39 states. [2020-08-21 14:53:13,102 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 39 states to 39 states and 56 transitions. [2020-08-21 14:53:13,103 INFO L78 Accepts]: Start accepts. Automaton has 39 states and 56 transitions. Word has length 22 [2020-08-21 14:53:13,103 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-21 14:53:13,103 INFO L479 AbstractCegarLoop]: Abstraction has 39 states and 56 transitions. [2020-08-21 14:53:13,103 INFO L480 AbstractCegarLoop]: Interpolant automaton has 6 states. [2020-08-21 14:53:13,104 INFO L276 IsEmpty]: Start isEmpty. Operand 39 states and 56 transitions. [2020-08-21 14:53:13,108 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 30 [2020-08-21 14:53:13,110 INFO L414 BasicCegarLoop]: Found error trace [2020-08-21 14:53:13,111 INFO L422 BasicCegarLoop]: trace histogram [3, 3, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-08-21 14:53:13,111 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2020-08-21 14:53:13,111 INFO L427 AbstractCegarLoop]: === Iteration 3 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-21 14:53:13,112 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-21 14:53:13,114 INFO L82 PathProgramCache]: Analyzing trace with hash 687949058, now seen corresponding path program 2 times [2020-08-21 14:53:13,114 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-21 14:53:13,115 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1730845445] [2020-08-21 14:53:13,115 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-21 14:53:13,141 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:13,174 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-21 14:53:13,174 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:13,179 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 7 [2020-08-21 14:53:13,196 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:13,218 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 3 [2020-08-21 14:53:13,223 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:13,241 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 3 [2020-08-21 14:53:13,245 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-21 14:53:13,252 INFO L134 CoverageAnalysis]: Checked inductivity of 15 backedges. 10 proven. 1 refuted. 0 times theorem prover too weak. 4 trivial. 0 not checked. [2020-08-21 14:53:13,252 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [1730845445] [2020-08-21 14:53:13,252 INFO L220 FreeRefinementEngine]: Constructing automaton from 0 perfect and 1 imperfect interpolant sequences. [2020-08-21 14:53:13,253 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [4] total 4 [2020-08-21 14:53:13,253 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1505666682] [2020-08-21 14:53:13,254 INFO L459 AbstractCegarLoop]: Interpolant automaton has 4 states [2020-08-21 14:53:13,254 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-21 14:53:13,254 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2020-08-21 14:53:13,255 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2020-08-21 14:53:13,255 INFO L87 Difference]: Start difference. First operand 39 states and 56 transitions. Second operand 4 states. [2020-08-21 14:53:13,323 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-21 14:53:13,323 INFO L93 Difference]: Finished difference Result 74 states and 133 transitions. [2020-08-21 14:53:13,324 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2020-08-21 14:53:13,324 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 29 [2020-08-21 14:53:13,324 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-21 14:53:13,327 INFO L225 Difference]: With dead ends: 74 [2020-08-21 14:53:13,327 INFO L226 Difference]: Without dead ends: 43 [2020-08-21 14:53:13,329 INFO L675 BasicCegarLoop]: 0 DeclaredPredicates, 14 GetRequests, 11 SyntacticMatches, 0 SemanticMatches, 3 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=9, Invalid=11, Unknown=0, NotChecked=0, Total=20 [2020-08-21 14:53:13,330 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 43 states. [2020-08-21 14:53:13,344 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 43 to 43. [2020-08-21 14:53:13,344 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 43 states. [2020-08-21 14:53:13,349 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 43 states to 43 states and 66 transitions. [2020-08-21 14:53:13,349 INFO L78 Accepts]: Start accepts. Automaton has 43 states and 66 transitions. Word has length 29 [2020-08-21 14:53:13,351 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-21 14:53:13,351 INFO L479 AbstractCegarLoop]: Abstraction has 43 states and 66 transitions. [2020-08-21 14:53:13,351 INFO L480 AbstractCegarLoop]: Interpolant automaton has 4 states. [2020-08-21 14:53:13,351 INFO L276 IsEmpty]: Start isEmpty. Operand 43 states and 66 transitions. [2020-08-21 14:53:13,355 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 43 [2020-08-21 14:53:13,355 INFO L414 BasicCegarLoop]: Found error trace [2020-08-21 14:53:13,356 INFO L422 BasicCegarLoop]: trace histogram [5, 5, 3, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-08-21 14:53:13,358 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable2 [2020-08-21 14:53:13,358 INFO L427 AbstractCegarLoop]: === Iteration 4 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-21 14:53:13,358 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-21 14:53:13,359 INFO L82 PathProgramCache]: Analyzing trace with hash -1711672813, now seen corresponding path program 1 times [2020-08-21 14:53:13,359 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-21 14:53:13,359 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [2111906176] [2020-08-21 14:53:13,360 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-21 14:53:13,421 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is sat [2020-08-21 14:53:13,423 INFO L174 FreeRefinementEngine]: Strategy FIXED_PREFERENCES found a feasible trace [2020-08-21 14:53:13,423 INFO L520 BasicCegarLoop]: Counterexample might be feasible [2020-08-21 14:53:13,433 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3 [2020-08-21 14:53:13,473 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction CFG 21.08 02:53:13 BoogieIcfgContainer [2020-08-21 14:53:13,473 INFO L132 PluginConnector]: ------------------------ END TraceAbstraction---------------------------- [2020-08-21 14:53:13,485 INFO L168 Benchmark]: Toolchain (without parser) took 2184.34 ms. Allocated memory was 141.6 MB in the beginning and 232.8 MB in the end (delta: 91.2 MB). Free memory was 103.9 MB in the beginning and 200.7 MB in the end (delta: -96.8 MB). Peak memory consumption was 79.8 MB. Max. memory is 7.1 GB. [2020-08-21 14:53:13,485 INFO L168 Benchmark]: CDTParser took 0.18 ms. Allocated memory is still 141.6 MB. Free memory was 121.8 MB in the beginning and 121.6 MB in the end (delta: 209.8 kB). There was no memory consumed. Max. memory is 7.1 GB. [2020-08-21 14:53:13,486 INFO L168 Benchmark]: CACSL2BoogieTranslator took 266.86 ms. Allocated memory is still 141.6 MB. Free memory was 103.5 MB in the beginning and 94.1 MB in the end (delta: 9.3 MB). Peak memory consumption was 9.3 MB. Max. memory is 7.1 GB. [2020-08-21 14:53:13,487 INFO L168 Benchmark]: Boogie Preprocessor took 152.57 ms. Allocated memory was 141.6 MB in the beginning and 207.6 MB in the end (delta: 66.1 MB). Free memory was 94.1 MB in the beginning and 186.4 MB in the end (delta: -92.2 MB). Peak memory consumption was 13.0 MB. Max. memory is 7.1 GB. [2020-08-21 14:53:13,488 INFO L168 Benchmark]: RCFGBuilder took 416.00 ms. Allocated memory is still 207.6 MB. Free memory was 186.4 MB in the beginning and 173.7 MB in the end (delta: 12.7 MB). Peak memory consumption was 12.7 MB. Max. memory is 7.1 GB. [2020-08-21 14:53:13,489 INFO L168 Benchmark]: TraceAbstraction took 1341.61 ms. Allocated memory was 207.6 MB in the beginning and 232.8 MB in the end (delta: 25.2 MB). Free memory was 173.1 MB in the beginning and 200.7 MB in the end (delta: -27.7 MB). Peak memory consumption was 82.9 MB. Max. memory is 7.1 GB. [2020-08-21 14:53:13,493 INFO L336 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * CDTParser took 0.18 ms. Allocated memory is still 141.6 MB. Free memory was 121.8 MB in the beginning and 121.6 MB in the end (delta: 209.8 kB). There was no memory consumed. Max. memory is 7.1 GB. * CACSL2BoogieTranslator took 266.86 ms. Allocated memory is still 141.6 MB. Free memory was 103.5 MB in the beginning and 94.1 MB in the end (delta: 9.3 MB). Peak memory consumption was 9.3 MB. Max. memory is 7.1 GB. * Boogie Preprocessor took 152.57 ms. Allocated memory was 141.6 MB in the beginning and 207.6 MB in the end (delta: 66.1 MB). Free memory was 94.1 MB in the beginning and 186.4 MB in the end (delta: -92.2 MB). Peak memory consumption was 13.0 MB. Max. memory is 7.1 GB. * RCFGBuilder took 416.00 ms. Allocated memory is still 207.6 MB. Free memory was 186.4 MB in the beginning and 173.7 MB in the end (delta: 12.7 MB). Peak memory consumption was 12.7 MB. Max. memory is 7.1 GB. * TraceAbstraction took 1341.61 ms. Allocated memory was 207.6 MB in the beginning and 232.8 MB in the end (delta: 25.2 MB). Free memory was 173.1 MB in the beginning and 200.7 MB in the end (delta: -27.7 MB). Peak memory consumption was 82.9 MB. Max. memory is 7.1 GB. * Results from de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: - CounterExampleResult [Line: 43]: a call of __VERIFIER_error() is reachable a call of __VERIFIER_error() is reachable We found a FailurePath: [L26] int m = __VERIFIER_nondet_int(); [L27] COND FALSE !(m < 0 || m > 3) [L32] int n = __VERIFIER_nondet_int(); [L33] COND FALSE !(n < 0 || n > 23) [L39] CALL, EXPR ackermann(m,n) [L15] COND FALSE !(m==0) [L18] COND TRUE n==0 [L19] CALL, EXPR ackermann(m-1,1) [L15] COND FALSE !(m==0) [L18] COND FALSE !(n==0) [L21] CALL, EXPR ackermann(m,n-1) [L15] COND FALSE !(m==0) [L18] COND TRUE n==0 [L19] CALL, EXPR ackermann(m-1,1) [L15] COND TRUE m==0 [L16] return n+1; [L19] RET, EXPR ackermann(m-1,1) [L19] return ackermann(m-1,1); [L21] RET, EXPR ackermann(m,n-1) [L21] CALL, EXPR ackermann(m-1,ackermann(m,n-1)) [L15] COND TRUE m==0 [L16] return n+1; [L21] RET, EXPR ackermann(m-1,ackermann(m,n-1)) [L21] return ackermann(m-1,ackermann(m,n-1)); [L19] RET, EXPR ackermann(m-1,1) [L19] return ackermann(m-1,1); [L39] RET, EXPR ackermann(m,n) [L39] int result = ackermann(m,n); [L40] COND FALSE !(m < 2 || result >= 4) [L43] __VERIFIER_error() - StatisticsResult: Ultimate Automizer benchmark data CFG has 4 procedures, 27 locations, 1 error locations. Started 1 CEGAR loops. VerificationResult: UNSAFE, OverallTime: 1.2s, OverallIterations: 4, TraceHistogramMax: 5, AutomataDifference: 0.5s, DeadEndRemovalTime: 0.0s, HoareAnnotationTime: 0.0s, InitialAbstractionConstructionTime: 0.0s, HoareTripleCheckerStatistics: 76 SDtfs, 42 SDslu, 135 SDs, 0 SdLazy, 128 SolverSat, 29 SolverUnsat, 0 SolverUnknown, 0 SolverNotchecked, 0.2s Time, PredicateUnifierStatistics: 0 DeclaredPredicates, 36 GetRequests, 23 SyntacticMatches, 0 SemanticMatches, 13 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 1 ImplicationChecksByTransitivity, 0.1s Time, 0.0s BasicInterpolantAutomatonTime, BiggestAbstraction: size=43occurred in iteration=3, traceCheckStatistics: No data available, InterpolantConsolidationStatistics: No data available, PathInvariantsStatistics: No data available, 0/0 InterpolantCoveringCapability, TotalInterpolationStatistics: No data available, 0.0s DumpTime, AutomataMinimizationStatistics: 0.0s AutomataMinimizationTime, 3 MinimizatonAttempts, 0 StatesRemovedByMinimization, 0 NontrivialMinimizations, HoareAnnotationStatistics: No data available, RefinementEngineStatistics: TRACE_CHECK: 0.0s SsaConstructionTime, 0.1s SatisfiabilityAnalysisTime, 0.3s InterpolantComputationTime, 108 NumberOfCodeBlocks, 108 NumberOfCodeBlocksAsserted, 4 NumberOfCheckSat, 63 ConstructedInterpolants, 0 QuantifiedInterpolants, 2359 SizeOfPredicates, 0 NumberOfNonLiveVariables, 0 ConjunctsInSsa, 0 ConjunctsInUnsatCore, 3 InterpolantComputations, 1 PerfectInterpolantSequences, 16/19 InterpolantCoveringCapability, INVARIANT_SYNTHESIS: No data available, INTERPOLANT_CONSOLIDATION: No data available, ABSTRACT_INTERPRETATION: No data available, PDR: No data available, ACCELERATED_INTERPOLATION: No data available, SIFA: No data available, ReuseStatistics: No data available RESULT: Ultimate proved your program to be incorrect! Received shutdown request...