./Ultimate.py --spec ../sv-benchmarks/c/properties/valid-memsafety.prp --file ../sv-benchmarks/c/pthread/fib_unsafe-6.i --full-output --architecture 32bit -------------------------------------------------------------------------------- Checking for memory safety (deref-memtrack) Using default analysis Version 3061b6dc Calling Ultimate with: /root/.sdkman/candidates/java/11.0.12-open/bin/java -Dosgi.configuration.area=/storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/config -Xmx15G -Xms4m -jar /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/plugins/org.eclipse.equinox.launcher_1.5.800.v20200727-1323.jar -data @noDefault -ultimatedata /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data -tc /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/config/AutomizerMemDerefMemtrack.xml -i ../sv-benchmarks/c/pthread/fib_unsafe-6.i -s /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/config/svcomp-DerefFreeMemtrack-32bit-Automizer_Default.epf --cacsl2boogietranslator.entry.function main --witnessprinter.witness.directory /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux --witnessprinter.witness.filename witness --witnessprinter.write.witness.besides.input.file false --witnessprinter.graph.data.specification CHECK( init(main()), LTL(G valid-free) ) CHECK( init(main()), LTL(G valid-deref) ) CHECK( init(main()), LTL(G valid-memtrack) ) --witnessprinter.graph.data.producer Automizer --witnessprinter.graph.data.architecture 32bit --witnessprinter.graph.data.programhash 854e371c98b43d805c328b457758892c4a501d7b326c2672c089850792494a4b --- Real Ultimate output --- This is Ultimate 0.2.5-tmp.dk.eval-assert-order-craig-3061b6d-m [2024-11-19 09:18:43,913 INFO L188 SettingsManager]: Resetting all preferences to default values... [2024-11-19 09:18:43,988 INFO L114 SettingsManager]: Loading settings from /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/config/svcomp-DerefFreeMemtrack-32bit-Automizer_Default.epf [2024-11-19 09:18:43,995 WARN L101 SettingsManager]: Preference file contains the following unknown settings: [2024-11-19 09:18:43,996 WARN L103 SettingsManager]: * de.uni_freiburg.informatik.ultimate.core.Log level for class [2024-11-19 09:18:44,014 INFO L130 SettingsManager]: Preferences different from defaults after loading the file: [2024-11-19 09:18:44,016 INFO L151 SettingsManager]: Preferences of UltimateCore differ from their defaults: [2024-11-19 09:18:44,017 INFO L153 SettingsManager]: * Log level for class=de.uni_freiburg.informatik.ultimate.lib.smtlibutils.quantifier.QuantifierPusher=ERROR; [2024-11-19 09:18:44,017 INFO L151 SettingsManager]: Preferences of Boogie Preprocessor differ from their defaults: [2024-11-19 09:18:44,019 INFO L153 SettingsManager]: * Use memory slicer=true [2024-11-19 09:18:44,019 INFO L151 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2024-11-19 09:18:44,019 INFO L153 SettingsManager]: * Ignore calls to procedures called more than once=ONLY_FOR_SEQUENTIAL_PROGRAMS [2024-11-19 09:18:44,020 INFO L151 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2024-11-19 09:18:44,020 INFO L153 SettingsManager]: * Create parallel compositions if possible=false [2024-11-19 09:18:44,022 INFO L153 SettingsManager]: * Use SBE=true [2024-11-19 09:18:44,022 INFO L151 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2024-11-19 09:18:44,022 INFO L153 SettingsManager]: * sizeof long=4 [2024-11-19 09:18:44,022 INFO L153 SettingsManager]: * Overapproximate operations on floating types=true [2024-11-19 09:18:44,023 INFO L153 SettingsManager]: * sizeof POINTER=4 [2024-11-19 09:18:44,023 INFO L153 SettingsManager]: * Check division by zero=IGNORE [2024-11-19 09:18:44,023 INFO L153 SettingsManager]: * Check for the main procedure if all allocated memory was freed=true [2024-11-19 09:18:44,026 INFO L153 SettingsManager]: * Bitprecise bitfields=true [2024-11-19 09:18:44,026 INFO L153 SettingsManager]: * SV-COMP memtrack compatibility mode=true [2024-11-19 09:18:44,026 INFO L153 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2024-11-19 09:18:44,026 INFO L153 SettingsManager]: * Adapt memory model on pointer casts if necessary=true [2024-11-19 09:18:44,027 INFO L153 SettingsManager]: * Allow undefined functions=false [2024-11-19 09:18:44,027 INFO L153 SettingsManager]: * Check unreachability of reach_error function=false [2024-11-19 09:18:44,027 INFO L153 SettingsManager]: * sizeof long double=12 [2024-11-19 09:18:44,027 INFO L153 SettingsManager]: * Use constant arrays=true [2024-11-19 09:18:44,028 INFO L151 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2024-11-19 09:18:44,028 INFO L153 SettingsManager]: * Size of a code block=SequenceOfStatements [2024-11-19 09:18:44,028 INFO L153 SettingsManager]: * Only consider context switches at boundaries of atomic blocks=true [2024-11-19 09:18:44,028 INFO L153 SettingsManager]: * SMT solver=External_DefaultMode [2024-11-19 09:18:44,028 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:4000 [2024-11-19 09:18:44,028 INFO L151 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2024-11-19 09:18:44,029 INFO L153 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2024-11-19 09:18:44,029 INFO L153 SettingsManager]: * Trace refinement strategy=CAMEL [2024-11-19 09:18:44,029 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2024-11-19 09:18:44,029 INFO L153 SettingsManager]: * Apply one-shot large block encoding in concurrent analysis=false [2024-11-19 09:18:44,029 INFO L153 SettingsManager]: * Automaton type used in concurrency analysis=PETRI_NET [2024-11-19 09:18:44,030 INFO L153 SettingsManager]: * Order on configurations for Petri net unfoldings=DBO [2024-11-19 09:18:44,030 INFO L153 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2024-11-19 09:18:44,031 INFO L153 SettingsManager]: * Looper check in Petri net analysis=SEMANTIC WARNING: An illegal reflective access operation has occurred WARNING: Illegal reflective access by com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 (file:/storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/plugins/com.sun.xml.bind_2.2.0.v201505121915.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int) WARNING: Please consider reporting this to the maintainers of com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations WARNING: All illegal access operations will be denied in a future release Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator: Entry function -> main Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness directory -> /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness filename -> witness Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Write witness besides input file -> false Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data specification -> CHECK( init(main()), LTL(G valid-free) ) CHECK( init(main()), LTL(G valid-deref) ) CHECK( init(main()), LTL(G valid-memtrack) ) Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data producer -> Automizer Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data architecture -> 32bit Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data programhash -> 854e371c98b43d805c328b457758892c4a501d7b326c2672c089850792494a4b [2024-11-19 09:18:44,224 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2024-11-19 09:18:44,241 INFO L261 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2024-11-19 09:18:44,243 INFO L217 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2024-11-19 09:18:44,244 INFO L270 PluginConnector]: Initializing CDTParser... [2024-11-19 09:18:44,244 INFO L274 PluginConnector]: CDTParser initialized [2024-11-19 09:18:44,245 INFO L431 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../sv-benchmarks/c/pthread/fib_unsafe-6.i [2024-11-19 09:18:45,483 INFO L533 CDTParser]: Created temporary CDT project at NULL [2024-11-19 09:18:45,681 INFO L384 CDTParser]: Found 1 translation units. [2024-11-19 09:18:45,681 INFO L180 CDTParser]: Scanning /storage/repos/ultimate/releaseScripts/default/sv-benchmarks/c/pthread/fib_unsafe-6.i [2024-11-19 09:18:45,691 INFO L427 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/6611f6802/13faec47ba364269891ec1424325225c/FLAG73230c90d [2024-11-19 09:18:45,703 INFO L435 CDTParser]: Successfully deleted /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/6611f6802/13faec47ba364269891ec1424325225c [2024-11-19 09:18:45,705 INFO L299 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2024-11-19 09:18:45,706 INFO L133 ToolchainWalker]: Walking toolchain with 6 elements. [2024-11-19 09:18:45,708 INFO L112 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2024-11-19 09:18:45,708 INFO L270 PluginConnector]: Initializing CACSL2BoogieTranslator... [2024-11-19 09:18:45,715 INFO L274 PluginConnector]: CACSL2BoogieTranslator initialized [2024-11-19 09:18:45,716 INFO L184 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 19.11 09:18:45" (1/1) ... [2024-11-19 09:18:45,716 INFO L204 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@25c0b39d and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:45, skipping insertion in model container [2024-11-19 09:18:45,717 INFO L184 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 19.11 09:18:45" (1/1) ... [2024-11-19 09:18:45,746 INFO L175 MainTranslator]: Built tables and reachable declarations [2024-11-19 09:18:46,033 INFO L210 PostProcessor]: Analyzing one entry point: main [2024-11-19 09:18:46,041 INFO L200 MainTranslator]: Completed pre-run [2024-11-19 09:18:46,086 INFO L210 PostProcessor]: Analyzing one entry point: main [2024-11-19 09:18:46,119 INFO L204 MainTranslator]: Completed translation [2024-11-19 09:18:46,120 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46 WrapperNode [2024-11-19 09:18:46,121 INFO L131 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2024-11-19 09:18:46,121 INFO L112 PluginConnector]: ------------------------Boogie Procedure Inliner---------------------------- [2024-11-19 09:18:46,122 INFO L270 PluginConnector]: Initializing Boogie Procedure Inliner... [2024-11-19 09:18:46,122 INFO L274 PluginConnector]: Boogie Procedure Inliner initialized [2024-11-19 09:18:46,127 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,141 INFO L184 PluginConnector]: Executing the observer Inliner from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,162 INFO L138 Inliner]: procedures = 164, calls = 21, calls flagged for inlining = 5, calls inlined = 5, statements flattened = 68 [2024-11-19 09:18:46,163 INFO L131 PluginConnector]: ------------------------ END Boogie Procedure Inliner---------------------------- [2024-11-19 09:18:46,164 INFO L112 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2024-11-19 09:18:46,164 INFO L270 PluginConnector]: Initializing Boogie Preprocessor... [2024-11-19 09:18:46,164 INFO L274 PluginConnector]: Boogie Preprocessor initialized [2024-11-19 09:18:46,172 INFO L184 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,172 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,176 INFO L184 PluginConnector]: Executing the observer MemorySlicer from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,195 INFO L175 MemorySlicer]: Split 2 memory accesses to 1 slices as follows [2]. 100 percent of accesses are in the largest equivalence class. The 2 initializations are split as follows [2]. The 0 writes are split as follows [0]. [2024-11-19 09:18:46,195 INFO L184 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,196 INFO L184 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,199 INFO L184 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,206 INFO L184 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,207 INFO L184 PluginConnector]: Executing the observer LTLStepAnnotator from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,209 INFO L184 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,211 INFO L131 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2024-11-19 09:18:46,215 INFO L112 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2024-11-19 09:18:46,215 INFO L270 PluginConnector]: Initializing RCFGBuilder... [2024-11-19 09:18:46,215 INFO L274 PluginConnector]: RCFGBuilder initialized [2024-11-19 09:18:46,216 INFO L184 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (1/1) ... [2024-11-19 09:18:46,221 INFO L173 SolverBuilder]: Constructing external solver with command: z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:4000 [2024-11-19 09:18:46,231 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2024-11-19 09:18:46,246 INFO L229 MonitoredProcess]: Starting monitored process 1 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:4000 (exit command is (exit), workingDir is null) [2024-11-19 09:18:46,249 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:4000 (1)] Waiting until timeout for monitored process [2024-11-19 09:18:46,292 INFO L130 BoogieDeclarations]: Found specification of procedure t1 [2024-11-19 09:18:46,293 INFO L138 BoogieDeclarations]: Found implementation of procedure t1 [2024-11-19 09:18:46,293 INFO L130 BoogieDeclarations]: Found specification of procedure t2 [2024-11-19 09:18:46,293 INFO L138 BoogieDeclarations]: Found implementation of procedure t2 [2024-11-19 09:18:46,293 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_atomic_begin [2024-11-19 09:18:46,293 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocInit [2024-11-19 09:18:46,293 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int#0 [2024-11-19 09:18:46,293 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_atomic_end [2024-11-19 09:18:46,293 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2024-11-19 09:18:46,293 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2024-11-19 09:18:46,295 WARN L207 CfgBuilder]: User set CodeBlockSize to SequenceOfStatements but program contains fork statements. Overwriting the user preferences and setting CodeBlockSize to OneNontrivialStatement. [2024-11-19 09:18:46,398 INFO L238 CfgBuilder]: Building ICFG [2024-11-19 09:18:46,400 INFO L264 CfgBuilder]: Building CFG for each procedure with an implementation [2024-11-19 09:18:46,527 INFO L283 CfgBuilder]: Omitted future-live optimization because the input is a concurrent program. [2024-11-19 09:18:46,528 INFO L287 CfgBuilder]: Performing block encoding [2024-11-19 09:18:46,622 INFO L311 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2024-11-19 09:18:46,623 INFO L316 CfgBuilder]: Removed 3 assume(true) statements. [2024-11-19 09:18:46,623 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 19.11 09:18:46 BoogieIcfgContainer [2024-11-19 09:18:46,623 INFO L131 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2024-11-19 09:18:46,626 INFO L112 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2024-11-19 09:18:46,626 INFO L270 PluginConnector]: Initializing TraceAbstraction... [2024-11-19 09:18:46,628 INFO L274 PluginConnector]: TraceAbstraction initialized [2024-11-19 09:18:46,629 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 19.11 09:18:45" (1/3) ... [2024-11-19 09:18:46,629 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@35ddafac and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 19.11 09:18:46, skipping insertion in model container [2024-11-19 09:18:46,629 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 09:18:46" (2/3) ... [2024-11-19 09:18:46,630 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@35ddafac and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 19.11 09:18:46, skipping insertion in model container [2024-11-19 09:18:46,630 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 19.11 09:18:46" (3/3) ... [2024-11-19 09:18:46,631 INFO L112 eAbstractionObserver]: Analyzing ICFG fib_unsafe-6.i [2024-11-19 09:18:46,643 INFO L214 ceAbstractionStarter]: Automizer settings: Hoare:None NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2024-11-19 09:18:46,643 INFO L154 ceAbstractionStarter]: Applying trace abstraction to program that has 2 error locations. [2024-11-19 09:18:46,644 INFO L489 ceAbstractionStarter]: Constructing petrified ICFG for 1 thread instances. [2024-11-19 09:18:46,704 INFO L143 ThreadInstanceAdder]: Constructed 0 joinOtherThreadTransitions. [2024-11-19 09:18:46,740 INFO L73 FinitePrefix]: Start finitePrefix. Operand has 36 places, 34 transitions, 76 flow [2024-11-19 09:18:46,757 INFO L124 PetriNetUnfolderBase]: 5/32 cut-off events. [2024-11-19 09:18:46,758 INFO L125 PetriNetUnfolderBase]: For 0/0 co-relation queries the response was YES. [2024-11-19 09:18:46,760 INFO L83 FinitePrefix]: Finished finitePrefix Result has 39 conditions, 32 events. 5/32 cut-off events. For 0/0 co-relation queries the response was YES. Maximal size of possible extension queue 4. Compared 37 event pairs, 0 based on Foata normal form. 0/25 useless extension candidates. Maximal degree in co-relation 29. Up to 2 conditions per place. [2024-11-19 09:18:46,760 INFO L82 GeneralOperation]: Start removeDead. Operand has 36 places, 34 transitions, 76 flow [2024-11-19 09:18:46,762 INFO L88 GeneralOperation]: Finished RemoveDead, result has has 34 places, 32 transitions, 70 flow [2024-11-19 09:18:46,768 INFO L332 AbstractCegarLoop]: ======== Iteration 0 == of CEGAR loop == AllErrorsAtOnce ======== [2024-11-19 09:18:46,773 INFO L333 AbstractCegarLoop]: Settings: SEPARATE_VIOLATION_CHECK=true, mInterprocedural=true, mMaxIterations=1000000, mWatchIteration=1000000, mArtifact=RCFG, mInterpolation=FPandBP, mInterpolantAutomaton=STRAIGHT_LINE, mDumpAutomata=false, mAutomataFormat=ATS_NUMERATE, mDumpPath=., mDeterminiation=PREDICATE_ABSTRACTION, mMinimize=MINIMIZE_SEVPA, mAutomataTypeConcurrency=PETRI_NET, mHoareTripleChecks=INCREMENTAL, mHoareAnnotationPositions=None, mDumpOnlyReuseAutomata=false, mLimitTraceHistogram=0, mErrorLocTimeLimit=0, mLimitPathProgramCount=0, mCollectInterpolantStatistics=true, mHeuristicEmptinessCheck=false, mHeuristicEmptinessCheckAStarHeuristic=ZERO, mHeuristicEmptinessCheckAStarHeuristicRandomSeed=1337, mHeuristicEmptinessCheckSmtFeatureScoringMethod=DAGSIZE, mSMTFeatureExtraction=false, mSMTFeatureExtractionDumpPath=., mOverrideInterpolantAutomaton=false, mMcrInterpolantMethod=WP, mPorIndependenceSettings=[Lde.uni_freiburg.informatik.ultimate.lib.tracecheckerutils.partialorder.independence.IndependenceSettings;@39e3d856, mLbeIndependenceSettings=[IndependenceType=SEMANTIC, AbstractionType=NONE, UseConditional=false, UseSemiCommutativity=true, Solver=Z3, SolverTimeout=1000ms] [2024-11-19 09:18:46,773 INFO L334 AbstractCegarLoop]: Starting to check reachability of 4 error locations. [2024-11-19 09:18:46,785 INFO L185 PetriNetUnfolderBase]: Found word, exiting Unfolder. [2024-11-19 09:18:46,786 INFO L124 PetriNetUnfolderBase]: 5/29 cut-off events. [2024-11-19 09:18:46,786 INFO L125 PetriNetUnfolderBase]: For 0/0 co-relation queries the response was YES. [2024-11-19 09:18:46,786 INFO L196 CegarLoopForPetriNet]: Found error trace [2024-11-19 09:18:46,787 INFO L204 CegarLoopForPetriNet]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2024-11-19 09:18:46,787 INFO L396 AbstractCegarLoop]: === Iteration 1 === Targeting ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK === [ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0INUSE_VIOLATIONSUFFICIENT_THREAD_INSTANCES (and 1 more)] === [2024-11-19 09:18:46,793 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2024-11-19 09:18:46,793 INFO L85 PathProgramCache]: Analyzing trace with hash 563650960, now seen corresponding path program 1 times [2024-11-19 09:18:46,800 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2024-11-19 09:18:46,800 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [655141524] [2024-11-19 09:18:46,800 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2024-11-19 09:18:46,801 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2024-11-19 09:18:46,897 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2024-11-19 09:18:47,033 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:47,034 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2024-11-19 09:18:47,034 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [655141524] [2024-11-19 09:18:47,035 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [655141524] provided 1 perfect and 0 imperfect interpolant sequences [2024-11-19 09:18:47,035 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2024-11-19 09:18:47,035 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [3] imperfect sequences [] total 3 [2024-11-19 09:18:47,037 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1243172902] [2024-11-19 09:18:47,037 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2024-11-19 09:18:47,043 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2024-11-19 09:18:47,049 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2024-11-19 09:18:47,070 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2024-11-19 09:18:47,071 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2024-11-19 09:18:47,073 INFO L467 CegarLoopForPetriNet]: Number of universal loopers: 13 out of 34 [2024-11-19 09:18:47,075 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 34 places, 32 transitions, 70 flow. Second operand has 3 states, 3 states have (on average 16.0) internal successors, (48), 3 states have internal predecessors, (48), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:47,076 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2024-11-19 09:18:47,076 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 13 of 34 [2024-11-19 09:18:47,077 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2024-11-19 09:18:47,174 INFO L124 PetriNetUnfolderBase]: 151/292 cut-off events. [2024-11-19 09:18:47,174 INFO L125 PetriNetUnfolderBase]: For 1/1 co-relation queries the response was YES. [2024-11-19 09:18:47,176 INFO L83 FinitePrefix]: Finished finitePrefix Result has 535 conditions, 292 events. 151/292 cut-off events. For 1/1 co-relation queries the response was YES. Maximal size of possible extension queue 20. Compared 993 event pairs, 20 based on Foata normal form. 18/296 useless extension candidates. Maximal degree in co-relation 521. Up to 172 conditions per place. [2024-11-19 09:18:47,178 INFO L140 encePairwiseOnDemand]: 29/34 looper letters, 22 selfloop transitions, 2 changer transitions 1/36 dead transitions. [2024-11-19 09:18:47,178 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 35 places, 36 transitions, 128 flow [2024-11-19 09:18:47,181 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2024-11-19 09:18:47,183 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 3 states. [2024-11-19 09:18:47,188 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 3 states to 3 states and 67 transitions. [2024-11-19 09:18:47,189 INFO L512 CegarLoopForPetriNet]: DFA transition density 0.6568627450980392 [2024-11-19 09:18:47,191 INFO L175 Difference]: Start difference. First operand has 34 places, 32 transitions, 70 flow. Second operand 3 states and 67 transitions. [2024-11-19 09:18:47,191 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 35 places, 36 transitions, 128 flow [2024-11-19 09:18:47,193 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 33 places, 36 transitions, 126 flow, removed 0 selfloop flow, removed 2 redundant places. [2024-11-19 09:18:47,195 INFO L231 Difference]: Finished difference. Result has 34 places, 29 transitions, 72 flow [2024-11-19 09:18:47,196 INFO L260 CegarLoopForPetriNet]: {PETRI_ALPHABET=34, PETRI_DIFFERENCE_MINUEND_FLOW=62, PETRI_DIFFERENCE_MINUEND_PLACES=31, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=29, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=1, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=27, PETRI_DIFFERENCE_SUBTRAHEND_STATES=3, PETRI_FLOW=72, PETRI_PLACES=34, PETRI_TRANSITIONS=29} [2024-11-19 09:18:47,200 INFO L277 CegarLoopForPetriNet]: 34 programPoint places, 0 predicate places. [2024-11-19 09:18:47,200 INFO L471 AbstractCegarLoop]: Abstraction has has 34 places, 29 transitions, 72 flow [2024-11-19 09:18:47,200 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 3 states, 3 states have (on average 16.0) internal successors, (48), 3 states have internal predecessors, (48), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:47,200 INFO L196 CegarLoopForPetriNet]: Found error trace [2024-11-19 09:18:47,201 INFO L204 CegarLoopForPetriNet]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2024-11-19 09:18:47,201 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2024-11-19 09:18:47,201 INFO L396 AbstractCegarLoop]: === Iteration 2 === Targeting ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK === [ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0INUSE_VIOLATIONSUFFICIENT_THREAD_INSTANCES (and 1 more)] === [2024-11-19 09:18:47,201 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2024-11-19 09:18:47,201 INFO L85 PathProgramCache]: Analyzing trace with hash -488978942, now seen corresponding path program 1 times [2024-11-19 09:18:47,201 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2024-11-19 09:18:47,202 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [955611599] [2024-11-19 09:18:47,202 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2024-11-19 09:18:47,202 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2024-11-19 09:18:47,215 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2024-11-19 09:18:47,284 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:47,285 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2024-11-19 09:18:47,285 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [955611599] [2024-11-19 09:18:47,286 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [955611599] provided 0 perfect and 1 imperfect interpolant sequences [2024-11-19 09:18:47,286 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [959790734] [2024-11-19 09:18:47,286 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2024-11-19 09:18:47,286 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:18:47,286 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2024-11-19 09:18:47,288 INFO L229 MonitoredProcess]: Starting monitored process 2 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2024-11-19 09:18:47,297 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (2)] Waiting until timeout for monitored process [2024-11-19 09:18:47,370 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2024-11-19 09:18:47,372 INFO L255 TraceCheckSpWp]: Trace formula consists of 104 conjuncts, 2 conjuncts are in the unsatisfiable core [2024-11-19 09:18:47,375 INFO L278 TraceCheckSpWp]: Computing forward predicates... [2024-11-19 09:18:47,405 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 1 trivial. 0 not checked. [2024-11-19 09:18:47,405 INFO L307 TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect [2024-11-19 09:18:47,405 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [959790734] provided 1 perfect and 0 imperfect interpolant sequences [2024-11-19 09:18:47,405 INFO L185 FreeRefinementEngine]: Found 1 perfect and 1 imperfect interpolant sequences. [2024-11-19 09:18:47,406 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [1] imperfect sequences [4] total 5 [2024-11-19 09:18:47,407 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1903790196] [2024-11-19 09:18:47,407 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2024-11-19 09:18:47,409 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2024-11-19 09:18:47,409 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2024-11-19 09:18:47,410 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2024-11-19 09:18:47,410 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=8, Invalid=12, Unknown=0, NotChecked=0, Total=20 [2024-11-19 09:18:47,411 INFO L467 CegarLoopForPetriNet]: Number of universal loopers: 12 out of 34 [2024-11-19 09:18:47,411 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 34 places, 29 transitions, 72 flow. Second operand has 3 states, 3 states have (on average 15.666666666666666) internal successors, (47), 3 states have internal predecessors, (47), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:47,411 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2024-11-19 09:18:47,411 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 12 of 34 [2024-11-19 09:18:47,411 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2024-11-19 09:18:47,460 INFO L124 PetriNetUnfolderBase]: 133/256 cut-off events. [2024-11-19 09:18:47,460 INFO L125 PetriNetUnfolderBase]: For 9/9 co-relation queries the response was YES. [2024-11-19 09:18:47,461 INFO L83 FinitePrefix]: Finished finitePrefix Result has 509 conditions, 256 events. 133/256 cut-off events. For 9/9 co-relation queries the response was YES. Maximal size of possible extension queue 16. Compared 816 event pairs, 80 based on Foata normal form. 9/248 useless extension candidates. Maximal degree in co-relation 494. Up to 204 conditions per place. [2024-11-19 09:18:47,462 INFO L140 encePairwiseOnDemand]: 32/34 looper letters, 16 selfloop transitions, 1 changer transitions 1/28 dead transitions. [2024-11-19 09:18:47,462 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 34 places, 28 transitions, 106 flow [2024-11-19 09:18:47,463 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2024-11-19 09:18:47,463 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 3 states. [2024-11-19 09:18:47,463 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 3 states to 3 states and 54 transitions. [2024-11-19 09:18:47,463 INFO L512 CegarLoopForPetriNet]: DFA transition density 0.5294117647058824 [2024-11-19 09:18:47,463 INFO L175 Difference]: Start difference. First operand has 34 places, 29 transitions, 72 flow. Second operand 3 states and 54 transitions. [2024-11-19 09:18:47,463 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 34 places, 28 transitions, 106 flow [2024-11-19 09:18:47,464 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 33 places, 28 transitions, 104 flow, removed 0 selfloop flow, removed 1 redundant places. [2024-11-19 09:18:47,464 INFO L231 Difference]: Finished difference. Result has 33 places, 27 transitions, 68 flow [2024-11-19 09:18:47,464 INFO L260 CegarLoopForPetriNet]: {PETRI_ALPHABET=34, PETRI_DIFFERENCE_MINUEND_FLOW=68, PETRI_DIFFERENCE_MINUEND_PLACES=31, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=28, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=1, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=27, PETRI_DIFFERENCE_SUBTRAHEND_STATES=3, PETRI_FLOW=68, PETRI_PLACES=33, PETRI_TRANSITIONS=27} [2024-11-19 09:18:47,465 INFO L277 CegarLoopForPetriNet]: 34 programPoint places, -1 predicate places. [2024-11-19 09:18:47,465 INFO L471 AbstractCegarLoop]: Abstraction has has 33 places, 27 transitions, 68 flow [2024-11-19 09:18:47,465 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 3 states, 3 states have (on average 15.666666666666666) internal successors, (47), 3 states have internal predecessors, (47), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:47,465 INFO L196 CegarLoopForPetriNet]: Found error trace [2024-11-19 09:18:47,465 INFO L204 CegarLoopForPetriNet]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2024-11-19 09:18:47,480 INFO L540 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (2)] Forceful destruction successful, exit code 0 [2024-11-19 09:18:47,666 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1,2 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:18:47,667 INFO L396 AbstractCegarLoop]: === Iteration 3 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK === [ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0INUSE_VIOLATIONSUFFICIENT_THREAD_INSTANCES (and 1 more)] === [2024-11-19 09:18:47,667 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2024-11-19 09:18:47,668 INFO L85 PathProgramCache]: Analyzing trace with hash -488977835, now seen corresponding path program 1 times [2024-11-19 09:18:47,668 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2024-11-19 09:18:47,668 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1137859831] [2024-11-19 09:18:47,668 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2024-11-19 09:18:47,668 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2024-11-19 09:18:47,681 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2024-11-19 09:18:47,724 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:47,724 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2024-11-19 09:18:47,724 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1137859831] [2024-11-19 09:18:47,724 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1137859831] provided 0 perfect and 1 imperfect interpolant sequences [2024-11-19 09:18:47,725 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [2037445133] [2024-11-19 09:18:47,725 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2024-11-19 09:18:47,725 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:18:47,725 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2024-11-19 09:18:47,726 INFO L229 MonitoredProcess]: Starting monitored process 3 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2024-11-19 09:18:47,728 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (3)] Waiting until timeout for monitored process [2024-11-19 09:18:47,781 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2024-11-19 09:18:47,782 INFO L255 TraceCheckSpWp]: Trace formula consists of 104 conjuncts, 3 conjuncts are in the unsatisfiable core [2024-11-19 09:18:47,783 INFO L278 TraceCheckSpWp]: Computing forward predicates... [2024-11-19 09:18:47,804 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:47,805 INFO L311 TraceCheckSpWp]: Computing backward predicates... [2024-11-19 09:18:47,820 INFO L134 CoverageAnalysis]: Checked inductivity of 1 backedges. 0 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:47,820 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [2037445133] provided 0 perfect and 2 imperfect interpolant sequences [2024-11-19 09:18:47,820 INFO L185 FreeRefinementEngine]: Found 0 perfect and 3 imperfect interpolant sequences. [2024-11-19 09:18:47,821 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [4, 4, 4] total 7 [2024-11-19 09:18:47,821 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1614687515] [2024-11-19 09:18:47,821 INFO L85 oduleStraightlineAll]: Using 3 imperfect interpolants to construct interpolant automaton [2024-11-19 09:18:47,821 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 7 states [2024-11-19 09:18:47,821 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2024-11-19 09:18:47,822 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 7 interpolants. [2024-11-19 09:18:47,822 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=21, Invalid=21, Unknown=0, NotChecked=0, Total=42 [2024-11-19 09:18:47,822 INFO L467 CegarLoopForPetriNet]: Number of universal loopers: 13 out of 34 [2024-11-19 09:18:47,822 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 33 places, 27 transitions, 68 flow. Second operand has 7 states, 7 states have (on average 15.142857142857142) internal successors, (106), 7 states have internal predecessors, (106), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:47,822 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2024-11-19 09:18:47,823 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 13 of 34 [2024-11-19 09:18:47,823 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2024-11-19 09:18:47,917 INFO L124 PetriNetUnfolderBase]: 169/310 cut-off events. [2024-11-19 09:18:47,918 INFO L125 PetriNetUnfolderBase]: For 6/6 co-relation queries the response was YES. [2024-11-19 09:18:47,919 INFO L83 FinitePrefix]: Finished finitePrefix Result has 636 conditions, 310 events. 169/310 cut-off events. For 6/6 co-relation queries the response was YES. Maximal size of possible extension queue 15. Compared 926 event pairs, 20 based on Foata normal form. 0/299 useless extension candidates. Maximal degree in co-relation 628. Up to 118 conditions per place. [2024-11-19 09:18:47,920 INFO L140 encePairwiseOnDemand]: 31/34 looper letters, 39 selfloop transitions, 5 changer transitions 0/54 dead transitions. [2024-11-19 09:18:47,920 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 37 places, 54 transitions, 216 flow [2024-11-19 09:18:47,920 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 6 states. [2024-11-19 09:18:47,920 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 6 states. [2024-11-19 09:18:47,921 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 6 states to 6 states and 125 transitions. [2024-11-19 09:18:47,921 INFO L512 CegarLoopForPetriNet]: DFA transition density 0.6127450980392157 [2024-11-19 09:18:47,935 INFO L175 Difference]: Start difference. First operand has 33 places, 27 transitions, 68 flow. Second operand 6 states and 125 transitions. [2024-11-19 09:18:47,935 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 37 places, 54 transitions, 216 flow [2024-11-19 09:18:47,935 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 36 places, 54 transitions, 215 flow, removed 0 selfloop flow, removed 1 redundant places. [2024-11-19 09:18:47,936 INFO L231 Difference]: Finished difference. Result has 39 places, 30 transitions, 103 flow [2024-11-19 09:18:47,936 INFO L260 CegarLoopForPetriNet]: {PETRI_ALPHABET=34, PETRI_DIFFERENCE_MINUEND_FLOW=67, PETRI_DIFFERENCE_MINUEND_PLACES=31, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=27, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=3, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=24, PETRI_DIFFERENCE_SUBTRAHEND_STATES=6, PETRI_FLOW=103, PETRI_PLACES=39, PETRI_TRANSITIONS=30} [2024-11-19 09:18:47,937 INFO L277 CegarLoopForPetriNet]: 34 programPoint places, 5 predicate places. [2024-11-19 09:18:47,937 INFO L471 AbstractCegarLoop]: Abstraction has has 39 places, 30 transitions, 103 flow [2024-11-19 09:18:47,937 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 7 states, 7 states have (on average 15.142857142857142) internal successors, (106), 7 states have internal predecessors, (106), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:47,937 INFO L196 CegarLoopForPetriNet]: Found error trace [2024-11-19 09:18:47,937 INFO L204 CegarLoopForPetriNet]: trace histogram [4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2024-11-19 09:18:47,949 INFO L540 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (3)] Forceful destruction successful, exit code 0 [2024-11-19 09:18:48,138 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 3 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true,SelfDestructingSolverStorable2 [2024-11-19 09:18:48,138 INFO L396 AbstractCegarLoop]: === Iteration 4 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK === [ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0INUSE_VIOLATIONSUFFICIENT_THREAD_INSTANCES (and 1 more)] === [2024-11-19 09:18:48,139 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2024-11-19 09:18:48,139 INFO L85 PathProgramCache]: Analyzing trace with hash 1932997219, now seen corresponding path program 2 times [2024-11-19 09:18:48,140 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2024-11-19 09:18:48,140 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1919597246] [2024-11-19 09:18:48,140 INFO L93 rtionOrderModulation]: Changing assertion order to OUTSIDE_LOOP_FIRST1 [2024-11-19 09:18:48,140 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2024-11-19 09:18:48,166 INFO L227 tOrderPrioritization]: Assert order OUTSIDE_LOOP_FIRST1 issued 2 check-sat command(s) [2024-11-19 09:18:48,166 INFO L228 tOrderPrioritization]: Conjunction of SSA is unsat [2024-11-19 09:18:48,239 INFO L134 CoverageAnalysis]: Checked inductivity of 10 backedges. 0 proven. 10 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:48,240 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2024-11-19 09:18:48,240 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1919597246] [2024-11-19 09:18:48,240 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1919597246] provided 0 perfect and 1 imperfect interpolant sequences [2024-11-19 09:18:48,240 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [14291846] [2024-11-19 09:18:48,240 INFO L93 rtionOrderModulation]: Changing assertion order to OUTSIDE_LOOP_FIRST1 [2024-11-19 09:18:48,240 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:18:48,240 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2024-11-19 09:18:48,242 INFO L229 MonitoredProcess]: Starting monitored process 4 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2024-11-19 09:18:48,244 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (4)] Waiting until timeout for monitored process [2024-11-19 09:18:48,298 INFO L227 tOrderPrioritization]: Assert order OUTSIDE_LOOP_FIRST1 issued 2 check-sat command(s) [2024-11-19 09:18:48,298 INFO L228 tOrderPrioritization]: Conjunction of SSA is unsat [2024-11-19 09:18:48,299 INFO L255 TraceCheckSpWp]: Trace formula consists of 131 conjuncts, 6 conjuncts are in the unsatisfiable core [2024-11-19 09:18:48,300 INFO L278 TraceCheckSpWp]: Computing forward predicates... [2024-11-19 09:18:48,316 INFO L134 CoverageAnalysis]: Checked inductivity of 10 backedges. 0 proven. 10 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:48,316 INFO L311 TraceCheckSpWp]: Computing backward predicates... [2024-11-19 09:18:48,372 INFO L134 CoverageAnalysis]: Checked inductivity of 10 backedges. 0 proven. 10 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:48,374 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [14291846] provided 0 perfect and 2 imperfect interpolant sequences [2024-11-19 09:18:48,374 INFO L185 FreeRefinementEngine]: Found 0 perfect and 3 imperfect interpolant sequences. [2024-11-19 09:18:48,374 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [7, 7, 7] total 13 [2024-11-19 09:18:48,375 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [284561881] [2024-11-19 09:18:48,375 INFO L85 oduleStraightlineAll]: Using 3 imperfect interpolants to construct interpolant automaton [2024-11-19 09:18:48,375 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 13 states [2024-11-19 09:18:48,375 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2024-11-19 09:18:48,375 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 13 interpolants. [2024-11-19 09:18:48,376 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=78, Invalid=78, Unknown=0, NotChecked=0, Total=156 [2024-11-19 09:18:48,378 INFO L467 CegarLoopForPetriNet]: Number of universal loopers: 13 out of 34 [2024-11-19 09:18:48,378 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 39 places, 30 transitions, 103 flow. Second operand has 13 states, 13 states have (on average 14.615384615384615) internal successors, (190), 13 states have internal predecessors, (190), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:48,378 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2024-11-19 09:18:48,378 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 13 of 34 [2024-11-19 09:18:48,379 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2024-11-19 09:18:48,526 INFO L124 PetriNetUnfolderBase]: 277/472 cut-off events. [2024-11-19 09:18:48,526 INFO L125 PetriNetUnfolderBase]: For 216/216 co-relation queries the response was YES. [2024-11-19 09:18:48,529 INFO L83 FinitePrefix]: Finished finitePrefix Result has 1171 conditions, 472 events. 277/472 cut-off events. For 216/216 co-relation queries the response was YES. Maximal size of possible extension queue 15. Compared 1325 event pairs, 20 based on Foata normal form. 54/524 useless extension candidates. Maximal degree in co-relation 1159. Up to 118 conditions per place. [2024-11-19 09:18:48,531 INFO L140 encePairwiseOnDemand]: 31/34 looper letters, 75 selfloop transitions, 11 changer transitions 0/96 dead transitions. [2024-11-19 09:18:48,531 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 50 places, 96 transitions, 431 flow [2024-11-19 09:18:48,532 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 12 states. [2024-11-19 09:18:48,532 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 12 states. [2024-11-19 09:18:48,533 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 12 states to 12 states and 248 transitions. [2024-11-19 09:18:48,535 INFO L512 CegarLoopForPetriNet]: DFA transition density 0.6078431372549019 [2024-11-19 09:18:48,536 INFO L175 Difference]: Start difference. First operand has 39 places, 30 transitions, 103 flow. Second operand 12 states and 248 transitions. [2024-11-19 09:18:48,536 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 50 places, 96 transitions, 431 flow [2024-11-19 09:18:48,538 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 49 places, 96 transitions, 417 flow, removed 6 selfloop flow, removed 1 redundant places. [2024-11-19 09:18:48,541 INFO L231 Difference]: Finished difference. Result has 55 places, 36 transitions, 173 flow [2024-11-19 09:18:48,541 INFO L260 CegarLoopForPetriNet]: {PETRI_ALPHABET=34, PETRI_DIFFERENCE_MINUEND_FLOW=89, PETRI_DIFFERENCE_MINUEND_PLACES=38, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=30, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=6, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=24, PETRI_DIFFERENCE_SUBTRAHEND_STATES=12, PETRI_FLOW=173, PETRI_PLACES=55, PETRI_TRANSITIONS=36} [2024-11-19 09:18:48,542 INFO L277 CegarLoopForPetriNet]: 34 programPoint places, 21 predicate places. [2024-11-19 09:18:48,542 INFO L471 AbstractCegarLoop]: Abstraction has has 55 places, 36 transitions, 173 flow [2024-11-19 09:18:48,542 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 13 states, 13 states have (on average 14.615384615384615) internal successors, (190), 13 states have internal predecessors, (190), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:48,542 INFO L196 CegarLoopForPetriNet]: Found error trace [2024-11-19 09:18:48,542 INFO L204 CegarLoopForPetriNet]: trace histogram [10, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2024-11-19 09:18:48,555 INFO L540 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (4)] Forceful destruction successful, exit code 0 [2024-11-19 09:18:48,743 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3,4 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:18:48,743 INFO L396 AbstractCegarLoop]: === Iteration 5 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK === [ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0INUSE_VIOLATIONSUFFICIENT_THREAD_INSTANCES (and 1 more)] === [2024-11-19 09:18:48,744 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2024-11-19 09:18:48,744 INFO L85 PathProgramCache]: Analyzing trace with hash 749587747, now seen corresponding path program 3 times [2024-11-19 09:18:48,744 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2024-11-19 09:18:48,744 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1519760622] [2024-11-19 09:18:48,744 INFO L93 rtionOrderModulation]: Changing assertion order to OUTSIDE_LOOP_FIRST2 [2024-11-19 09:18:48,744 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2024-11-19 09:18:48,781 INFO L227 tOrderPrioritization]: Assert order OUTSIDE_LOOP_FIRST2 issued 6 check-sat command(s) [2024-11-19 09:18:48,782 INFO L228 tOrderPrioritization]: Conjunction of SSA is unsat [2024-11-19 09:18:48,936 INFO L134 CoverageAnalysis]: Checked inductivity of 55 backedges. 0 proven. 55 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:48,936 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2024-11-19 09:18:48,936 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1519760622] [2024-11-19 09:18:48,936 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1519760622] provided 0 perfect and 1 imperfect interpolant sequences [2024-11-19 09:18:48,936 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [911828058] [2024-11-19 09:18:48,936 INFO L93 rtionOrderModulation]: Changing assertion order to OUTSIDE_LOOP_FIRST2 [2024-11-19 09:18:48,936 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:18:48,937 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2024-11-19 09:18:48,938 INFO L229 MonitoredProcess]: Starting monitored process 5 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2024-11-19 09:18:48,939 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (5)] Waiting until timeout for monitored process [2024-11-19 09:18:48,999 INFO L227 tOrderPrioritization]: Assert order OUTSIDE_LOOP_FIRST2 issued 6 check-sat command(s) [2024-11-19 09:18:48,999 INFO L228 tOrderPrioritization]: Conjunction of SSA is unsat [2024-11-19 09:18:49,000 INFO L255 TraceCheckSpWp]: Trace formula consists of 185 conjuncts, 12 conjuncts are in the unsatisfiable core [2024-11-19 09:18:49,002 INFO L278 TraceCheckSpWp]: Computing forward predicates... [2024-11-19 09:18:49,029 INFO L134 CoverageAnalysis]: Checked inductivity of 55 backedges. 0 proven. 55 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:49,029 INFO L311 TraceCheckSpWp]: Computing backward predicates... [2024-11-19 09:18:49,156 INFO L134 CoverageAnalysis]: Checked inductivity of 55 backedges. 0 proven. 55 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:49,156 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [911828058] provided 0 perfect and 2 imperfect interpolant sequences [2024-11-19 09:18:49,156 INFO L185 FreeRefinementEngine]: Found 0 perfect and 3 imperfect interpolant sequences. [2024-11-19 09:18:49,156 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [13, 13, 13] total 17 [2024-11-19 09:18:49,156 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1344736815] [2024-11-19 09:18:49,156 INFO L85 oduleStraightlineAll]: Using 3 imperfect interpolants to construct interpolant automaton [2024-11-19 09:18:49,157 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 17 states [2024-11-19 09:18:49,157 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2024-11-19 09:18:49,157 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 17 interpolants. [2024-11-19 09:18:49,157 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=136, Invalid=136, Unknown=0, NotChecked=0, Total=272 [2024-11-19 09:18:49,158 INFO L467 CegarLoopForPetriNet]: Number of universal loopers: 13 out of 34 [2024-11-19 09:18:49,158 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 55 places, 36 transitions, 173 flow. Second operand has 17 states, 17 states have (on average 14.529411764705882) internal successors, (247), 17 states have internal predecessors, (247), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:49,158 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2024-11-19 09:18:49,158 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 13 of 34 [2024-11-19 09:18:49,158 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2024-11-19 09:18:49,314 INFO L124 PetriNetUnfolderBase]: 349/580 cut-off events. [2024-11-19 09:18:49,314 INFO L125 PetriNetUnfolderBase]: For 1620/1620 co-relation queries the response was YES. [2024-11-19 09:18:49,316 INFO L83 FinitePrefix]: Finished finitePrefix Result has 1655 conditions, 580 events. 349/580 cut-off events. For 1620/1620 co-relation queries the response was YES. Maximal size of possible extension queue 15. Compared 1591 event pairs, 20 based on Foata normal form. 36/614 useless extension candidates. Maximal degree in co-relation 1636. Up to 118 conditions per place. [2024-11-19 09:18:49,318 INFO L140 encePairwiseOnDemand]: 31/34 looper letters, 99 selfloop transitions, 15 changer transitions 0/124 dead transitions. [2024-11-19 09:18:49,318 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 70 places, 124 transitions, 601 flow [2024-11-19 09:18:49,318 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 16 states. [2024-11-19 09:18:49,318 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 16 states. [2024-11-19 09:18:49,319 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 16 states to 16 states and 326 transitions. [2024-11-19 09:18:49,319 INFO L512 CegarLoopForPetriNet]: DFA transition density 0.5992647058823529 [2024-11-19 09:18:49,319 INFO L175 Difference]: Start difference. First operand has 55 places, 36 transitions, 173 flow. Second operand 16 states and 326 transitions. [2024-11-19 09:18:49,320 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 70 places, 124 transitions, 601 flow [2024-11-19 09:18:49,324 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 65 places, 124 transitions, 545 flow, removed 23 selfloop flow, removed 5 redundant places. [2024-11-19 09:18:49,325 INFO L231 Difference]: Finished difference. Result has 69 places, 40 transitions, 197 flow [2024-11-19 09:18:49,325 INFO L260 CegarLoopForPetriNet]: {PETRI_ALPHABET=34, PETRI_DIFFERENCE_MINUEND_FLOW=125, PETRI_DIFFERENCE_MINUEND_PLACES=50, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=36, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=12, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=24, PETRI_DIFFERENCE_SUBTRAHEND_STATES=16, PETRI_FLOW=197, PETRI_PLACES=69, PETRI_TRANSITIONS=40} [2024-11-19 09:18:49,326 INFO L277 CegarLoopForPetriNet]: 34 programPoint places, 35 predicate places. [2024-11-19 09:18:49,326 INFO L471 AbstractCegarLoop]: Abstraction has has 69 places, 40 transitions, 197 flow [2024-11-19 09:18:49,326 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 17 states, 17 states have (on average 14.529411764705882) internal successors, (247), 17 states have internal predecessors, (247), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:49,326 INFO L196 CegarLoopForPetriNet]: Found error trace [2024-11-19 09:18:49,326 INFO L204 CegarLoopForPetriNet]: trace histogram [14, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2024-11-19 09:18:49,338 INFO L540 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (5)] Forceful destruction successful, exit code 0 [2024-11-19 09:18:49,530 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable4,5 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:18:49,531 INFO L396 AbstractCegarLoop]: === Iteration 6 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK === [ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0INUSE_VIOLATIONSUFFICIENT_THREAD_INSTANCES (and 1 more)] === [2024-11-19 09:18:49,531 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2024-11-19 09:18:49,531 INFO L85 PathProgramCache]: Analyzing trace with hash 350665123, now seen corresponding path program 4 times [2024-11-19 09:18:49,531 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2024-11-19 09:18:49,535 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1408595925] [2024-11-19 09:18:49,535 INFO L93 rtionOrderModulation]: Changing assertion order to TERMS_WITH_SMALL_CONSTANTS_FIRST [2024-11-19 09:18:49,535 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2024-11-19 09:18:49,572 INFO L227 tOrderPrioritization]: Assert order TERMS_WITH_SMALL_CONSTANTS_FIRST issued 0 check-sat command(s) [2024-11-19 09:18:49,572 INFO L228 tOrderPrioritization]: Conjunction of SSA is unsat [2024-11-19 09:18:50,378 INFO L134 CoverageAnalysis]: Checked inductivity of 105 backedges. 0 proven. 105 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:50,379 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2024-11-19 09:18:50,379 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1408595925] [2024-11-19 09:18:50,380 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1408595925] provided 0 perfect and 1 imperfect interpolant sequences [2024-11-19 09:18:50,380 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [611651355] [2024-11-19 09:18:50,380 INFO L93 rtionOrderModulation]: Changing assertion order to TERMS_WITH_SMALL_CONSTANTS_FIRST [2024-11-19 09:18:50,380 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:18:50,380 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2024-11-19 09:18:50,382 INFO L229 MonitoredProcess]: Starting monitored process 6 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2024-11-19 09:18:50,383 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (6)] Waiting until timeout for monitored process [2024-11-19 09:18:50,446 INFO L227 tOrderPrioritization]: Assert order TERMS_WITH_SMALL_CONSTANTS_FIRST issued 0 check-sat command(s) [2024-11-19 09:18:50,446 INFO L228 tOrderPrioritization]: Conjunction of SSA is unsat [2024-11-19 09:18:50,447 INFO L255 TraceCheckSpWp]: Trace formula consists of 221 conjuncts, 53 conjuncts are in the unsatisfiable core [2024-11-19 09:18:50,449 INFO L278 TraceCheckSpWp]: Computing forward predicates... [2024-11-19 09:18:51,215 INFO L134 CoverageAnalysis]: Checked inductivity of 105 backedges. 78 proven. 27 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:51,215 INFO L311 TraceCheckSpWp]: Computing backward predicates... [2024-11-19 09:18:52,098 INFO L134 CoverageAnalysis]: Checked inductivity of 105 backedges. 0 proven. 105 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:18:52,099 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [611651355] provided 0 perfect and 2 imperfect interpolant sequences [2024-11-19 09:18:52,099 INFO L185 FreeRefinementEngine]: Found 0 perfect and 3 imperfect interpolant sequences. [2024-11-19 09:18:52,099 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [21, 21, 21] total 61 [2024-11-19 09:18:52,099 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1707411265] [2024-11-19 09:18:52,099 INFO L85 oduleStraightlineAll]: Using 3 imperfect interpolants to construct interpolant automaton [2024-11-19 09:18:52,100 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 62 states [2024-11-19 09:18:52,100 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2024-11-19 09:18:52,101 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 62 interpolants. [2024-11-19 09:18:52,102 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=477, Invalid=3305, Unknown=0, NotChecked=0, Total=3782 [2024-11-19 09:18:52,130 INFO L467 CegarLoopForPetriNet]: Number of universal loopers: 7 out of 34 [2024-11-19 09:18:52,130 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 69 places, 40 transitions, 197 flow. Second operand has 62 states, 62 states have (on average 8.258064516129032) internal successors, (512), 62 states have internal predecessors, (512), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:18:52,131 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2024-11-19 09:18:52,131 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 7 of 34 [2024-11-19 09:18:52,131 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2024-11-19 09:19:07,030 INFO L124 PetriNetUnfolderBase]: 15442/25419 cut-off events. [2024-11-19 09:19:07,031 INFO L125 PetriNetUnfolderBase]: For 54099/54099 co-relation queries the response was YES. [2024-11-19 09:19:07,076 INFO L83 FinitePrefix]: Finished finitePrefix Result has 67201 conditions, 25419 events. 15442/25419 cut-off events. For 54099/54099 co-relation queries the response was YES. Maximal size of possible extension queue 392. Compared 165378 event pairs, 242 based on Foata normal form. 0/25094 useless extension candidates. Maximal degree in co-relation 67178. Up to 3219 conditions per place. [2024-11-19 09:19:07,165 INFO L140 encePairwiseOnDemand]: 23/34 looper letters, 568 selfloop transitions, 575 changer transitions 701/1848 dead transitions. [2024-11-19 09:19:07,165 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 243 places, 1848 transitions, 10950 flow [2024-11-19 09:19:07,166 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 175 states. [2024-11-19 09:19:07,166 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 175 states. [2024-11-19 09:19:07,171 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 175 states to 175 states and 2684 transitions. [2024-11-19 09:19:07,173 INFO L512 CegarLoopForPetriNet]: DFA transition density 0.4510924369747899 [2024-11-19 09:19:07,174 INFO L175 Difference]: Start difference. First operand has 69 places, 40 transitions, 197 flow. Second operand 175 states and 2684 transitions. [2024-11-19 09:19:07,174 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 243 places, 1848 transitions, 10950 flow [2024-11-19 09:19:07,250 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 232 places, 1848 transitions, 9424 flow, removed 442 selfloop flow, removed 11 redundant places. [2024-11-19 09:19:07,265 INFO L231 Difference]: Finished difference. Result has 302 places, 667 transitions, 4023 flow [2024-11-19 09:19:07,265 INFO L260 CegarLoopForPetriNet]: {PETRI_ALPHABET=34, PETRI_DIFFERENCE_MINUEND_FLOW=149, PETRI_DIFFERENCE_MINUEND_PLACES=58, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=40, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=20, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=19, PETRI_DIFFERENCE_SUBTRAHEND_STATES=175, PETRI_FLOW=4023, PETRI_PLACES=302, PETRI_TRANSITIONS=667} [2024-11-19 09:19:07,267 INFO L277 CegarLoopForPetriNet]: 34 programPoint places, 268 predicate places. [2024-11-19 09:19:07,267 INFO L471 AbstractCegarLoop]: Abstraction has has 302 places, 667 transitions, 4023 flow [2024-11-19 09:19:07,268 INFO L472 AbstractCegarLoop]: INTERPOLANT automaton has has 62 states, 62 states have (on average 8.258064516129032) internal successors, (512), 62 states have internal predecessors, (512), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:19:07,269 INFO L196 CegarLoopForPetriNet]: Found error trace [2024-11-19 09:19:07,269 INFO L204 CegarLoopForPetriNet]: trace histogram [14, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2024-11-19 09:19:07,282 INFO L552 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (6)] Ended with exit code 0 [2024-11-19 09:19:07,473 WARN L453 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable5,6 /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:19:07,474 INFO L396 AbstractCegarLoop]: === Iteration 7 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK === [ULTIMATE.startErr1ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0ASSERT_VIOLATIONMEMORY_LEAK, ULTIMATE.startErr0INUSE_VIOLATIONSUFFICIENT_THREAD_INSTANCES (and 1 more)] === [2024-11-19 09:19:07,474 INFO L157 PredicateUnifier]: Initialized classic predicate unifier [2024-11-19 09:19:07,475 INFO L85 PathProgramCache]: Analyzing trace with hash -600576193, now seen corresponding path program 1 times [2024-11-19 09:19:07,475 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2024-11-19 09:19:07,475 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1781781338] [2024-11-19 09:19:07,475 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2024-11-19 09:19:07,476 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2024-11-19 09:19:07,507 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2024-11-19 09:19:08,394 INFO L134 CoverageAnalysis]: Checked inductivity of 107 backedges. 0 proven. 107 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:19:08,394 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2024-11-19 09:19:08,394 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1781781338] [2024-11-19 09:19:08,394 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1781781338] provided 0 perfect and 1 imperfect interpolant sequences [2024-11-19 09:19:08,394 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [2084886531] [2024-11-19 09:19:08,395 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2024-11-19 09:19:08,395 INFO L173 SolverBuilder]: Constructing external solver with command: z3 -smt2 -in SMTLIB2_COMPLIANT=true [2024-11-19 09:19:08,395 INFO L189 MonitoredProcess]: No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 [2024-11-19 09:19:08,396 INFO L229 MonitoredProcess]: Starting monitored process 7 with /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) [2024-11-19 09:19:08,397 INFO L327 MonitoredProcess]: [MP /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 -smt2 -in SMTLIB2_COMPLIANT=true (7)] Waiting until timeout for monitored process [2024-11-19 09:19:08,453 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2024-11-19 09:19:08,454 INFO L255 TraceCheckSpWp]: Trace formula consists of 235 conjuncts, 55 conjuncts are in the unsatisfiable core [2024-11-19 09:19:08,456 INFO L278 TraceCheckSpWp]: Computing forward predicates... [2024-11-19 09:19:09,121 INFO L134 CoverageAnalysis]: Checked inductivity of 107 backedges. 78 proven. 29 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:19:09,121 INFO L311 TraceCheckSpWp]: Computing backward predicates... [2024-11-19 09:19:09,970 INFO L134 CoverageAnalysis]: Checked inductivity of 107 backedges. 0 proven. 107 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2024-11-19 09:19:09,970 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleZ3 [2084886531] provided 0 perfect and 2 imperfect interpolant sequences [2024-11-19 09:19:09,971 INFO L185 FreeRefinementEngine]: Found 0 perfect and 3 imperfect interpolant sequences. [2024-11-19 09:19:09,971 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [23, 23, 23] total 67 [2024-11-19 09:19:09,971 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [16023681] [2024-11-19 09:19:09,971 INFO L85 oduleStraightlineAll]: Using 3 imperfect interpolants to construct interpolant automaton [2024-11-19 09:19:09,972 INFO L548 AbstractCegarLoop]: INTERPOLANT automaton has 68 states [2024-11-19 09:19:09,974 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2024-11-19 09:19:09,974 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 68 interpolants. [2024-11-19 09:19:09,975 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=537, Invalid=4019, Unknown=0, NotChecked=0, Total=4556 [2024-11-19 09:19:10,205 INFO L467 CegarLoopForPetriNet]: Number of universal loopers: 7 out of 34 [2024-11-19 09:19:10,206 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 302 places, 667 transitions, 4023 flow. Second operand has 68 states, 68 states have (on average 8.323529411764707) internal successors, (566), 68 states have internal predecessors, (566), 0 states have call successors, (0), 0 states have call predecessors, (0), 0 states have return successors, (0), 0 states have call predecessors, (0), 0 states have call successors, (0) [2024-11-19 09:19:10,206 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2024-11-19 09:19:10,206 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 7 of 34 [2024-11-19 09:19:10,206 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand