/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 enumeration-timeout=5 --traceabstraction.additional.smt.options interpolation-heuristic=WIDESTAMONGSMALL --traceabstraction.additional.smt.options tolerance=0.4 -s ../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf -i ../../../trunk/examples/svcomp/recursive/Ackermann02.c -------------------------------------------------------------------------------- This is Ultimate 0.1.25-5644d1e-m [2020-08-19 00:17:53,919 INFO L177 SettingsManager]: Resetting all preferences to default values... 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[2020-08-19 00:17:53,986 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2020-08-19 00:17:53,988 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2020-08-19 00:17:53,991 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2020-08-19 00:17:53,992 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2020-08-19 00:17:53,994 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2020-08-19 00:17:53,995 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2020-08-19 00:17:53,996 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2020-08-19 00:17:54,003 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2020-08-19 00:17:54,005 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2020-08-19 00:17:54,006 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2020-08-19 00:17:54,008 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2020-08-19 00:17:54,010 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2020-08-19 00:17:54,021 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... 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[2020-08-19 00:17:54,036 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2020-08-19 00:17:54,036 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2020-08-19 00:17:54,037 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2020-08-19 00:17:54,041 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 [2020-08-19 00:17:54,080 INFO L113 SettingsManager]: Loading preferences was successful [2020-08-19 00:17:54,082 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2020-08-19 00:17:54,083 INFO L136 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2020-08-19 00:17:54,084 INFO L138 SettingsManager]: * Create parallel compositions if possible=false [2020-08-19 00:17:54,084 INFO L138 SettingsManager]: * Use SBE=true [2020-08-19 00:17:54,084 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2020-08-19 00:17:54,084 INFO L138 SettingsManager]: * sizeof long=4 [2020-08-19 00:17:54,084 INFO L138 SettingsManager]: * Overapproximate operations on floating types=true [2020-08-19 00:17:54,085 INFO L138 SettingsManager]: * sizeof POINTER=4 [2020-08-19 00:17:54,085 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2020-08-19 00:17:54,085 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2020-08-19 00:17:54,085 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2020-08-19 00:17:54,086 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2020-08-19 00:17:54,086 INFO L138 SettingsManager]: * sizeof long double=12 [2020-08-19 00:17:54,086 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2020-08-19 00:17:54,086 INFO L138 SettingsManager]: * Use constant arrays=true [2020-08-19 00:17:54,086 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2020-08-19 00:17:54,086 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2020-08-19 00:17:54,087 INFO L138 SettingsManager]: * Size of a code block=SequenceOfStatements [2020-08-19 00:17:54,087 INFO L138 SettingsManager]: * To the following directory=./dump/ [2020-08-19 00:17:54,087 INFO L138 SettingsManager]: * SMT solver=External_DefaultMode [2020-08-19 00:17:54,087 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-08-19 00:17:54,087 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2020-08-19 00:17:54,089 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2020-08-19 00:17:54,089 INFO L138 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2020-08-19 00:17:54,089 INFO L138 SettingsManager]: * Trace refinement strategy=CAMEL [2020-08-19 00:17:54,090 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2020-08-19 00:17:54,090 INFO L138 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2020-08-19 00:17:54,090 INFO L138 SettingsManager]: * Trace refinement exception blacklist=NONE [2020-08-19 00:17:54,090 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 -> enumeration-timeout=5;interpolation-heuristic=WIDESTAMONGSMALL;tolerance=0.4; Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Additional SMT options -> enumeration-timeout=5;interpolation-heuristic=WIDESTAMONGSMALL;tolerance=0.4; Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Additional SMT options -> enumeration-timeout=5;interpolation-heuristic=WIDESTAMONGSMALL;tolerance=0.4; [2020-08-19 00:17:54,370 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2020-08-19 00:17:54,384 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2020-08-19 00:17:54,391 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2020-08-19 00:17:54,393 INFO L271 PluginConnector]: Initializing CDTParser... [2020-08-19 00:17:54,393 INFO L275 PluginConnector]: CDTParser initialized [2020-08-19 00:17:54,394 INFO L429 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/recursive/Ackermann02.c [2020-08-19 00:17:54,466 INFO L220 CDTParser]: Created temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/03120e553/5ed9a961a41b4f08b397312291d4d9db/FLAGfa1d861e7 [2020-08-19 00:17:54,891 INFO L306 CDTParser]: Found 1 translation units. [2020-08-19 00:17:54,892 INFO L160 CDTParser]: Scanning /storage/repos/ultimate-2/trunk/examples/svcomp/recursive/Ackermann02.c [2020-08-19 00:17:54,898 INFO L349 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/03120e553/5ed9a961a41b4f08b397312291d4d9db/FLAGfa1d861e7 [2020-08-19 00:17:55,280 INFO L357 CDTParser]: Successfully deleted /storage/repos/ultimate-2/releaseScripts/default/UAutomizer-linux/data/03120e553/5ed9a961a41b4f08b397312291d4d9db [2020-08-19 00:17:55,288 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2020-08-19 00:17:55,289 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2020-08-19 00:17:55,290 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2020-08-19 00:17:55,290 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2020-08-19 00:17:55,293 INFO L275 PluginConnector]: CACSL2BoogieTranslator initialized [2020-08-19 00:17:55,294 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,296 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@12925ca7 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55, skipping insertion in model container [2020-08-19 00:17:55,296 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,303 INFO L145 MainTranslator]: Starting translation in SV-COMP mode [2020-08-19 00:17:55,319 INFO L178 MainTranslator]: Built tables and reachable declarations [2020-08-19 00:17:55,485 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-08-19 00:17:55,491 INFO L203 MainTranslator]: Completed pre-run [2020-08-19 00:17:55,512 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-08-19 00:17:55,527 INFO L208 MainTranslator]: Completed translation [2020-08-19 00:17:55,529 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55 WrapperNode [2020-08-19 00:17:55,529 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2020-08-19 00:17:55,530 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2020-08-19 00:17:55,530 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2020-08-19 00:17:55,530 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2020-08-19 00:17:55,541 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,541 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,545 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,546 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,549 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,551 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,552 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (1/1) ... [2020-08-19 00:17:55,553 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2020-08-19 00:17:55,554 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2020-08-19 00:17:55,554 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2020-08-19 00:17:55,554 INFO L275 PluginConnector]: RCFGBuilder initialized [2020-08-19 00:17:55,555 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (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 [2020-08-19 00:17:55,680 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2020-08-19 00:17:55,680 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2020-08-19 00:17:55,680 INFO L138 BoogieDeclarations]: Found implementation of procedure ackermann [2020-08-19 00:17:55,680 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2020-08-19 00:17:55,681 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_error [2020-08-19 00:17:55,681 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_int [2020-08-19 00:17:55,681 INFO L130 BoogieDeclarations]: Found specification of procedure ackermann [2020-08-19 00:17:55,681 INFO L130 BoogieDeclarations]: Found specification of procedure main [2020-08-19 00:17:55,681 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2020-08-19 00:17:55,681 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2020-08-19 00:17:55,861 INFO L290 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2020-08-19 00:17:55,861 INFO L295 CfgBuilder]: Removed 0 assume(true) statements. [2020-08-19 00:17:55,865 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 19.08 12:17:55 BoogieIcfgContainer [2020-08-19 00:17:55,865 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2020-08-19 00:17:55,867 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2020-08-19 00:17:55,867 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2020-08-19 00:17:55,870 INFO L275 PluginConnector]: TraceAbstraction initialized [2020-08-19 00:17:55,870 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 19.08 12:17:55" (1/3) ... [2020-08-19 00:17:55,871 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@1acb3058 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 19.08 12:17:55, skipping insertion in model container [2020-08-19 00:17:55,871 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.08 12:17:55" (2/3) ... [2020-08-19 00:17:55,872 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@1acb3058 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 19.08 12:17:55, skipping insertion in model container [2020-08-19 00:17:55,872 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 19.08 12:17:55" (3/3) ... [2020-08-19 00:17:55,873 INFO L109 eAbstractionObserver]: Analyzing ICFG Ackermann02.c [2020-08-19 00:17:55,884 INFO L157 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:Craig_NestedInterpolation Determinization: PREDICATE_ABSTRACTION [2020-08-19 00:17:55,892 INFO L169 ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations. [2020-08-19 00:17:55,905 INFO L251 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2020-08-19 00:17:55,963 INFO L375 AbstractCegarLoop]: Interprodecural is true [2020-08-19 00:17:55,964 INFO L376 AbstractCegarLoop]: Hoare is true [2020-08-19 00:17:55,964 INFO L377 AbstractCegarLoop]: Compute interpolants for Craig_NestedInterpolation [2020-08-19 00:17:55,964 INFO L378 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2020-08-19 00:17:55,964 INFO L379 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2020-08-19 00:17:55,965 INFO L380 AbstractCegarLoop]: Difference is false [2020-08-19 00:17:55,965 INFO L381 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2020-08-19 00:17:55,965 INFO L385 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2020-08-19 00:17:55,989 INFO L276 IsEmpty]: Start isEmpty. Operand 27 states. [2020-08-19 00:17:55,999 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 16 [2020-08-19 00:17:55,999 INFO L414 BasicCegarLoop]: Found error trace [2020-08-19 00:17:56,000 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-08-19 00:17:56,001 INFO L427 AbstractCegarLoop]: === Iteration 1 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-19 00:17:56,006 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-19 00:17:56,007 INFO L82 PathProgramCache]: Analyzing trace with hash -1796234678, now seen corresponding path program 1 times [2020-08-19 00:17:56,017 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-19 00:17:56,017 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [430815273] [2020-08-19 00:17:56,018 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-19 00:17:56,102 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,163 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-19 00:17:56,165 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,169 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 7 [2020-08-19 00:17:56,181 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,258 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-08-19 00:17:56,260 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [430815273] [2020-08-19 00:17:56,263 INFO L220 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-08-19 00:17:56,263 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2020-08-19 00:17:56,264 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [469816505] [2020-08-19 00:17:56,269 INFO L459 AbstractCegarLoop]: Interpolant automaton has 5 states [2020-08-19 00:17:56,269 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-19 00:17:56,283 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2020-08-19 00:17:56,284 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2020-08-19 00:17:56,286 INFO L87 Difference]: Start difference. First operand 27 states. Second operand 5 states. [2020-08-19 00:17:56,423 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-19 00:17:56,423 INFO L93 Difference]: Finished difference Result 55 states and 77 transitions. [2020-08-19 00:17:56,425 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2020-08-19 00:17:56,426 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 15 [2020-08-19 00:17:56,427 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-19 00:17:56,445 INFO L225 Difference]: With dead ends: 55 [2020-08-19 00:17:56,445 INFO L226 Difference]: Without dead ends: 28 [2020-08-19 00:17:56,452 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 [2020-08-19 00:17:56,469 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 28 states. [2020-08-19 00:17:56,493 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 28 to 28. [2020-08-19 00:17:56,494 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 28 states. [2020-08-19 00:17:56,496 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 28 states to 28 states and 35 transitions. [2020-08-19 00:17:56,498 INFO L78 Accepts]: Start accepts. Automaton has 28 states and 35 transitions. Word has length 15 [2020-08-19 00:17:56,498 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-19 00:17:56,498 INFO L479 AbstractCegarLoop]: Abstraction has 28 states and 35 transitions. [2020-08-19 00:17:56,498 INFO L480 AbstractCegarLoop]: Interpolant automaton has 5 states. [2020-08-19 00:17:56,498 INFO L276 IsEmpty]: Start isEmpty. Operand 28 states and 35 transitions. [2020-08-19 00:17:56,501 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 23 [2020-08-19 00:17:56,501 INFO L414 BasicCegarLoop]: Found error trace [2020-08-19 00:17:56,501 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] [2020-08-19 00:17:56,502 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2020-08-19 00:17:56,502 INFO L427 AbstractCegarLoop]: === Iteration 2 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-19 00:17:56,502 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-19 00:17:56,503 INFO L82 PathProgramCache]: Analyzing trace with hash -895156504, now seen corresponding path program 1 times [2020-08-19 00:17:56,503 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-19 00:17:56,503 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [577947001] [2020-08-19 00:17:56,504 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-19 00:17:56,523 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,559 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-19 00:17:56,560 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,562 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 7 [2020-08-19 00:17:56,570 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,607 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 3 [2020-08-19 00:17:56,611 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,632 INFO L134 CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 2 refuted. 0 times theorem prover too weak. 2 trivial. 0 not checked. [2020-08-19 00:17:56,632 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [577947001] [2020-08-19 00:17:56,633 INFO L220 FreeRefinementEngine]: Constructing automaton from 0 perfect and 1 imperfect interpolant sequences. [2020-08-19 00:17:56,633 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [6] total 6 [2020-08-19 00:17:56,633 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1408270548] [2020-08-19 00:17:56,635 INFO L459 AbstractCegarLoop]: Interpolant automaton has 6 states [2020-08-19 00:17:56,635 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-19 00:17:56,636 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 6 interpolants. [2020-08-19 00:17:56,636 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=10, Invalid=20, Unknown=0, NotChecked=0, Total=30 [2020-08-19 00:17:56,636 INFO L87 Difference]: Start difference. First operand 28 states and 35 transitions. Second operand 6 states. [2020-08-19 00:17:56,771 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-19 00:17:56,771 INFO L93 Difference]: Finished difference Result 43 states and 60 transitions. [2020-08-19 00:17:56,772 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 7 states. [2020-08-19 00:17:56,772 INFO L78 Accepts]: Start accepts. Automaton has 6 states. Word has length 22 [2020-08-19 00:17:56,773 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-19 00:17:56,775 INFO L225 Difference]: With dead ends: 43 [2020-08-19 00:17:56,775 INFO L226 Difference]: Without dead ends: 39 [2020-08-19 00:17:56,777 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 [2020-08-19 00:17:56,777 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 39 states. [2020-08-19 00:17:56,787 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 39 to 39. [2020-08-19 00:17:56,787 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 39 states. [2020-08-19 00:17:56,789 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 39 states to 39 states and 56 transitions. [2020-08-19 00:17:56,789 INFO L78 Accepts]: Start accepts. Automaton has 39 states and 56 transitions. Word has length 22 [2020-08-19 00:17:56,790 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-19 00:17:56,790 INFO L479 AbstractCegarLoop]: Abstraction has 39 states and 56 transitions. [2020-08-19 00:17:56,790 INFO L480 AbstractCegarLoop]: Interpolant automaton has 6 states. [2020-08-19 00:17:56,790 INFO L276 IsEmpty]: Start isEmpty. Operand 39 states and 56 transitions. [2020-08-19 00:17:56,792 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 30 [2020-08-19 00:17:56,792 INFO L414 BasicCegarLoop]: Found error trace [2020-08-19 00:17:56,792 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] [2020-08-19 00:17:56,793 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2020-08-19 00:17:56,793 INFO L427 AbstractCegarLoop]: === Iteration 3 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-19 00:17:56,793 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-19 00:17:56,793 INFO L82 PathProgramCache]: Analyzing trace with hash 687949058, now seen corresponding path program 2 times [2020-08-19 00:17:56,793 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-19 00:17:56,794 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [2068741977] [2020-08-19 00:17:56,794 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-19 00:17:56,809 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,823 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-08-19 00:17:56,824 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,826 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 7 [2020-08-19 00:17:56,839 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,861 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 3 [2020-08-19 00:17:56,870 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,888 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 3 [2020-08-19 00:17:56,891 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-08-19 00:17:56,898 INFO L134 CoverageAnalysis]: Checked inductivity of 15 backedges. 10 proven. 1 refuted. 0 times theorem prover too weak. 4 trivial. 0 not checked. [2020-08-19 00:17:56,899 INFO L354 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [2068741977] [2020-08-19 00:17:56,899 INFO L220 FreeRefinementEngine]: Constructing automaton from 0 perfect and 1 imperfect interpolant sequences. [2020-08-19 00:17:56,899 INFO L233 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [4] total 4 [2020-08-19 00:17:56,900 INFO L156 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1866930235] [2020-08-19 00:17:56,900 INFO L459 AbstractCegarLoop]: Interpolant automaton has 4 states [2020-08-19 00:17:56,901 INFO L143 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-08-19 00:17:56,901 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2020-08-19 00:17:56,901 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2020-08-19 00:17:56,901 INFO L87 Difference]: Start difference. First operand 39 states and 56 transitions. Second operand 4 states. [2020-08-19 00:17:56,956 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-08-19 00:17:56,956 INFO L93 Difference]: Finished difference Result 74 states and 133 transitions. [2020-08-19 00:17:56,957 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2020-08-19 00:17:56,957 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 29 [2020-08-19 00:17:56,957 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-08-19 00:17:56,960 INFO L225 Difference]: With dead ends: 74 [2020-08-19 00:17:56,960 INFO L226 Difference]: Without dead ends: 43 [2020-08-19 00:17:56,962 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 [2020-08-19 00:17:56,963 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 43 states. [2020-08-19 00:17:56,974 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 43 to 43. [2020-08-19 00:17:56,974 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 43 states. [2020-08-19 00:17:56,976 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 43 states to 43 states and 66 transitions. [2020-08-19 00:17:56,976 INFO L78 Accepts]: Start accepts. Automaton has 43 states and 66 transitions. Word has length 29 [2020-08-19 00:17:56,977 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-08-19 00:17:56,977 INFO L479 AbstractCegarLoop]: Abstraction has 43 states and 66 transitions. [2020-08-19 00:17:56,977 INFO L480 AbstractCegarLoop]: Interpolant automaton has 4 states. [2020-08-19 00:17:56,977 INFO L276 IsEmpty]: Start isEmpty. Operand 43 states and 66 transitions. [2020-08-19 00:17:56,996 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 43 [2020-08-19 00:17:56,996 INFO L414 BasicCegarLoop]: Found error trace [2020-08-19 00:17:56,996 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] [2020-08-19 00:17:56,996 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable2 [2020-08-19 00:17:56,997 INFO L427 AbstractCegarLoop]: === Iteration 4 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-08-19 00:17:56,997 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-08-19 00:17:56,997 INFO L82 PathProgramCache]: Analyzing trace with hash -1711672813, now seen corresponding path program 1 times [2020-08-19 00:17:56,998 INFO L163 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-08-19 00:17:56,998 INFO L354 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1115692041] [2020-08-19 00:17:56,998 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-08-19 00:17:57,019 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is sat [2020-08-19 00:17:57,021 INFO L174 FreeRefinementEngine]: Strategy FIXED_PREFERENCES found a feasible trace [2020-08-19 00:17:57,022 INFO L520 BasicCegarLoop]: Counterexample might be feasible [2020-08-19 00:17:57,026 WARN L516 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3 [2020-08-19 00:17:57,044 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction CFG 19.08 12:17:57 BoogieIcfgContainer [2020-08-19 00:17:57,044 INFO L132 PluginConnector]: ------------------------ END TraceAbstraction---------------------------- [2020-08-19 00:17:57,047 INFO L168 Benchmark]: Toolchain (without parser) took 1757.15 ms. Allocated memory was 142.6 MB in the beginning and 232.8 MB in the end (delta: 90.2 MB). Free memory was 106.1 MB in the beginning and 200.9 MB in the end (delta: -94.9 MB). There was no memory consumed. Max. memory is 7.1 GB. [2020-08-19 00:17:57,048 INFO L168 Benchmark]: CDTParser took 0.20 ms. Allocated memory is still 142.6 MB. Free memory was 124.1 MB in the beginning and 123.9 MB in the end (delta: 209.8 kB). There was no memory consumed. Max. memory is 7.1 GB. [2020-08-19 00:17:57,049 INFO L168 Benchmark]: CACSL2BoogieTranslator took 239.66 ms. Allocated memory is still 142.6 MB. Free memory was 105.9 MB in the beginning and 96.4 MB in the end (delta: 9.5 MB). Peak memory consumption was 9.5 MB. Max. memory is 7.1 GB. [2020-08-19 00:17:57,050 INFO L168 Benchmark]: Boogie Preprocessor took 23.45 ms. Allocated memory is still 142.6 MB. Free memory was 96.4 MB in the beginning and 95.0 MB in the end (delta: 1.4 MB). Peak memory consumption was 1.4 MB. Max. memory is 7.1 GB. [2020-08-19 00:17:57,051 INFO L168 Benchmark]: RCFGBuilder took 311.68 ms. Allocated memory was 142.6 MB in the beginning and 205.0 MB in the end (delta: 62.4 MB). Free memory was 95.0 MB in the beginning and 172.0 MB in the end (delta: -77.0 MB). Peak memory consumption was 12.6 MB. Max. memory is 7.1 GB. [2020-08-19 00:17:57,052 INFO L168 Benchmark]: TraceAbstraction took 1177.69 ms. Allocated memory was 205.0 MB in the beginning and 232.8 MB in the end (delta: 27.8 MB). Free memory was 171.4 MB in the beginning and 200.9 MB in the end (delta: -29.5 MB). There was no memory consumed. Max. memory is 7.1 GB. [2020-08-19 00:17:57,056 INFO L336 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * CDTParser took 0.20 ms. Allocated memory is still 142.6 MB. Free memory was 124.1 MB in the beginning and 123.9 MB in the end (delta: 209.8 kB). There was no memory consumed. Max. memory is 7.1 GB. * CACSL2BoogieTranslator took 239.66 ms. Allocated memory is still 142.6 MB. Free memory was 105.9 MB in the beginning and 96.4 MB in the end (delta: 9.5 MB). Peak memory consumption was 9.5 MB. Max. memory is 7.1 GB. * Boogie Preprocessor took 23.45 ms. Allocated memory is still 142.6 MB. Free memory was 96.4 MB in the beginning and 95.0 MB in the end (delta: 1.4 MB). Peak memory consumption was 1.4 MB. Max. memory is 7.1 GB. * RCFGBuilder took 311.68 ms. Allocated memory was 142.6 MB in the beginning and 205.0 MB in the end (delta: 62.4 MB). Free memory was 95.0 MB in the beginning and 172.0 MB in the end (delta: -77.0 MB). Peak memory consumption was 12.6 MB. Max. memory is 7.1 GB. * TraceAbstraction took 1177.69 ms. Allocated memory was 205.0 MB in the beginning and 232.8 MB in the end (delta: 27.8 MB). Free memory was 171.4 MB in the beginning and 200.9 MB in the end (delta: -29.5 MB). There was no memory consumed. 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: 1.0s, OverallIterations: 4, TraceHistogramMax: 5, AutomataDifference: 0.3s, 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, 0.1s 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, 0.0s 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...