./Ultimate.py --spec ../../sv-benchmarks/c/properties/valid-memsafety.prp --file ../../sv-benchmarks/c/weaver/parallel-bakery-4.wvr.c --full-output --architecture 32bit -------------------------------------------------------------------------------- Checking for memory safety (deref-memtrack) Using default analysis Version 527bcce2 Calling Ultimate with: /usr/lib/jvm/java-1.11.0-openjdk-amd64/bin/java -Dosgi.configuration.area=/tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/data/config -Xmx15G -Xms4m -jar /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/plugins/org.eclipse.equinox.launcher_1.5.800.v20200727-1323.jar -data @noDefault -ultimatedata /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/data -tc /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/config/AutomizerMemDerefMemtrack.xml -i ../../sv-benchmarks/c/weaver/parallel-bakery-4.wvr.c -s /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/config/svcomp-DerefFreeMemtrack-32bit-Automizer_Default.epf --cacsl2boogietranslator.entry.function main --witnessprinter.witness.directory /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx --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 a42fdc99fbc54512a7829bd297e0f02fe251a511098f304812399f6e9de1d8b6 --- Real Ultimate output --- This is Ultimate 0.2.3-dev-527bcce [2023-11-21 22:05:13,107 INFO L188 SettingsManager]: Resetting all preferences to default values... [2023-11-21 22:05:13,195 INFO L114 SettingsManager]: Loading settings from /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/config/svcomp-DerefFreeMemtrack-32bit-Automizer_Default.epf [2023-11-21 22:05:13,202 WARN L101 SettingsManager]: Preference file contains the following unknown settings: [2023-11-21 22:05:13,203 WARN L103 SettingsManager]: * de.uni_freiburg.informatik.ultimate.core.Log level for class [2023-11-21 22:05:13,236 INFO L130 SettingsManager]: Preferences different from defaults after loading the file: [2023-11-21 22:05:13,237 INFO L151 SettingsManager]: Preferences of UltimateCore differ from their defaults: [2023-11-21 22:05:13,238 INFO L153 SettingsManager]: * Log level for class=de.uni_freiburg.informatik.ultimate.lib.smtlibutils.quantifier.QuantifierPusher=ERROR; [2023-11-21 22:05:13,239 INFO L151 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2023-11-21 22:05:13,240 INFO L153 SettingsManager]: * Ignore calls to procedures called more than once=ONLY_FOR_SEQUENTIAL_PROGRAMS [2023-11-21 22:05:13,241 INFO L151 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2023-11-21 22:05:13,242 INFO L153 SettingsManager]: * Create parallel compositions if possible=false [2023-11-21 22:05:13,243 INFO L153 SettingsManager]: * Use SBE=true [2023-11-21 22:05:13,243 INFO L151 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2023-11-21 22:05:13,244 INFO L153 SettingsManager]: * sizeof long=4 [2023-11-21 22:05:13,245 INFO L153 SettingsManager]: * Overapproximate operations on floating types=true [2023-11-21 22:05:13,246 INFO L153 SettingsManager]: * sizeof POINTER=4 [2023-11-21 22:05:13,246 INFO L153 SettingsManager]: * Check division by zero=IGNORE [2023-11-21 22:05:13,247 INFO L153 SettingsManager]: * Check for the main procedure if all allocated memory was freed=true [2023-11-21 22:05:13,248 INFO L153 SettingsManager]: * Bitprecise bitfields=true [2023-11-21 22:05:13,249 INFO L153 SettingsManager]: * SV-COMP memtrack compatibility mode=true [2023-11-21 22:05:13,250 INFO L153 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2023-11-21 22:05:13,250 INFO L153 SettingsManager]: * Adapt memory model on pointer casts if necessary=true [2023-11-21 22:05:13,251 INFO L153 SettingsManager]: * Check unreachability of reach_error function=false [2023-11-21 22:05:13,252 INFO L153 SettingsManager]: * sizeof long double=12 [2023-11-21 22:05:13,252 INFO L153 SettingsManager]: * Use constant arrays=true [2023-11-21 22:05:13,253 INFO L151 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2023-11-21 22:05:13,254 INFO L153 SettingsManager]: * Size of a code block=SequenceOfStatements [2023-11-21 22:05:13,255 INFO L153 SettingsManager]: * Only consider context switches at boundaries of atomic blocks=true [2023-11-21 22:05:13,255 INFO L153 SettingsManager]: * SMT solver=External_DefaultMode [2023-11-21 22:05:13,256 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2023-11-21 22:05:13,256 INFO L151 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2023-11-21 22:05:13,257 INFO L153 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2023-11-21 22:05:13,258 INFO L153 SettingsManager]: * Trace refinement strategy=CAMEL [2023-11-21 22:05:13,258 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2023-11-21 22:05:13,259 INFO L153 SettingsManager]: * Apply one-shot large block encoding in concurrent analysis=false [2023-11-21 22:05:13,259 INFO L153 SettingsManager]: * Automaton type used in concurrency analysis=PETRI_NET [2023-11-21 22:05:13,260 INFO L153 SettingsManager]: * Order on configurations for Petri net unfoldings=DBO [2023-11-21 22:05:13,260 INFO L153 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2023-11-21 22:05:13,260 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:/tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/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$1 WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations WARNING: All illegal access operations will be denied in a future release Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator: Entry function -> main Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness directory -> /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness filename -> witness Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Write witness besides input file -> false Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data specification -> CHECK( init(main()), LTL(G valid-free) ) CHECK( init(main()), LTL(G valid-deref) ) CHECK( init(main()), LTL(G valid-memtrack) ) Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data producer -> Automizer Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data architecture -> 32bit Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data programhash -> a42fdc99fbc54512a7829bd297e0f02fe251a511098f304812399f6e9de1d8b6 [2023-11-21 22:05:13,609 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2023-11-21 22:05:13,650 INFO L261 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2023-11-21 22:05:13,653 INFO L217 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2023-11-21 22:05:13,655 INFO L270 PluginConnector]: Initializing CDTParser... [2023-11-21 22:05:13,656 INFO L274 PluginConnector]: CDTParser initialized [2023-11-21 22:05:13,657 INFO L431 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/../../sv-benchmarks/c/weaver/parallel-bakery-4.wvr.c [2023-11-21 22:05:16,953 INFO L533 CDTParser]: Created temporary CDT project at NULL [2023-11-21 22:05:17,244 INFO L384 CDTParser]: Found 1 translation units. [2023-11-21 22:05:17,245 INFO L180 CDTParser]: Scanning /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/sv-benchmarks/c/weaver/parallel-bakery-4.wvr.c [2023-11-21 22:05:17,258 INFO L427 CDTParser]: About to delete temporary CDT project at /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/data/abf276ffd/d2a2ca8ffaae4d8b8dbd93fc6cb4d2d7/FLAG28110daf3 [2023-11-21 22:05:17,276 INFO L435 CDTParser]: Successfully deleted /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/data/abf276ffd/d2a2ca8ffaae4d8b8dbd93fc6cb4d2d7 [2023-11-21 22:05:17,280 INFO L299 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2023-11-21 22:05:17,282 INFO L133 ToolchainWalker]: Walking toolchain with 6 elements. [2023-11-21 22:05:17,284 INFO L112 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2023-11-21 22:05:17,284 INFO L270 PluginConnector]: Initializing CACSL2BoogieTranslator... [2023-11-21 22:05:17,291 INFO L274 PluginConnector]: CACSL2BoogieTranslator initialized [2023-11-21 22:05:17,292 INFO L184 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,294 INFO L204 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@5217c43b and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17, skipping insertion in model container [2023-11-21 22:05:17,294 INFO L184 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,336 INFO L177 MainTranslator]: Built tables and reachable declarations [2023-11-21 22:05:17,659 INFO L209 PostProcessor]: Analyzing one entry point: main [2023-11-21 22:05:17,671 INFO L202 MainTranslator]: Completed pre-run [2023-11-21 22:05:17,720 INFO L209 PostProcessor]: Analyzing one entry point: main [2023-11-21 22:05:17,732 WARN L675 CHandler]: The function __VERIFIER_atomic_begin is called, but not defined or handled by StandardFunctionHandler. [2023-11-21 22:05:17,732 WARN L675 CHandler]: The function __VERIFIER_atomic_end is called, but not defined or handled by StandardFunctionHandler. [2023-11-21 22:05:17,742 INFO L206 MainTranslator]: Completed translation [2023-11-21 22:05:17,743 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17 WrapperNode [2023-11-21 22:05:17,743 INFO L131 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2023-11-21 22:05:17,744 INFO L112 PluginConnector]: ------------------------Boogie Procedure Inliner---------------------------- [2023-11-21 22:05:17,745 INFO L270 PluginConnector]: Initializing Boogie Procedure Inliner... [2023-11-21 22:05:17,745 INFO L274 PluginConnector]: Boogie Procedure Inliner initialized [2023-11-21 22:05:17,754 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,779 INFO L184 PluginConnector]: Executing the observer Inliner from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,823 INFO L138 Inliner]: procedures = 23, calls = 177, calls flagged for inlining = 29, calls inlined = 29, statements flattened = 410 [2023-11-21 22:05:17,823 INFO L131 PluginConnector]: ------------------------ END Boogie Procedure Inliner---------------------------- [2023-11-21 22:05:17,824 INFO L112 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2023-11-21 22:05:17,824 INFO L270 PluginConnector]: Initializing Boogie Preprocessor... [2023-11-21 22:05:17,825 INFO L274 PluginConnector]: Boogie Preprocessor initialized [2023-11-21 22:05:17,835 INFO L184 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,835 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,842 INFO L184 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,843 INFO L184 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,856 INFO L184 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,861 INFO L184 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,864 INFO L184 PluginConnector]: Executing the observer LTLStepAnnotator from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,866 INFO L184 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,872 INFO L131 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2023-11-21 22:05:17,873 INFO L112 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2023-11-21 22:05:17,874 INFO L270 PluginConnector]: Initializing RCFGBuilder... [2023-11-21 22:05:17,874 INFO L274 PluginConnector]: RCFGBuilder initialized [2023-11-21 22:05:17,875 INFO L184 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (1/1) ... [2023-11-21 22:05:17,882 INFO L173 SolverBuilder]: Constructing external solver with command: z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2023-11-21 22:05:17,898 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/z3 [2023-11-21 22:05:17,912 INFO L229 MonitoredProcess]: Starting monitored process 1 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null) [2023-11-21 22:05:17,955 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_719c689b-2e9a-4d5c-b5b7-24e6209e8c3b/bin/uautomizer-verify-bycVGegfSx/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (1)] Waiting until timeout for monitored process [2023-11-21 22:05:17,984 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocInit [2023-11-21 22:05:17,984 INFO L130 BoogieDeclarations]: Found specification of procedure thread1 [2023-11-21 22:05:17,984 INFO L138 BoogieDeclarations]: Found implementation of procedure thread1 [2023-11-21 22:05:17,984 INFO L130 BoogieDeclarations]: Found specification of procedure thread2 [2023-11-21 22:05:17,984 INFO L138 BoogieDeclarations]: Found implementation of procedure thread2 [2023-11-21 22:05:17,985 INFO L130 BoogieDeclarations]: Found specification of procedure thread3 [2023-11-21 22:05:17,985 INFO L138 BoogieDeclarations]: Found implementation of procedure thread3 [2023-11-21 22:05:17,985 INFO L130 BoogieDeclarations]: Found specification of procedure thread4 [2023-11-21 22:05:17,985 INFO L138 BoogieDeclarations]: Found implementation of procedure thread4 [2023-11-21 22:05:17,985 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int [2023-11-21 22:05:17,985 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocOnStack [2023-11-21 22:05:17,986 INFO L130 BoogieDeclarations]: Found specification of procedure write~int [2023-11-21 22:05:17,986 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_atomic_end [2023-11-21 22:05:17,986 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_atomic_begin [2023-11-21 22:05:17,986 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2023-11-21 22:05:17,986 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2023-11-21 22:05:17,986 INFO L130 BoogieDeclarations]: Found specification of procedure read~int [2023-11-21 22:05:17,987 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.dealloc [2023-11-21 22:05:17,989 WARN L212 CfgBuilder]: User set CodeBlockSize to SequenceOfStatements but program contains fork statements. Overwriting the user preferences and setting CodeBlockSize to OneNontrivialStatement [2023-11-21 22:05:18,112 INFO L240 CfgBuilder]: Building ICFG [2023-11-21 22:05:18,114 INFO L266 CfgBuilder]: Building CFG for each procedure with an implementation [2023-11-21 22:05:18,859 INFO L281 CfgBuilder]: Performing block encoding [2023-11-21 22:05:19,609 INFO L303 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2023-11-21 22:05:19,610 INFO L308 CfgBuilder]: Removed 0 assume(true) statements. [2023-11-21 22:05:19,612 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 21.11 10:05:19 BoogieIcfgContainer [2023-11-21 22:05:19,613 INFO L131 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2023-11-21 22:05:19,618 INFO L112 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2023-11-21 22:05:19,619 INFO L270 PluginConnector]: Initializing TraceAbstraction... [2023-11-21 22:05:19,622 INFO L274 PluginConnector]: TraceAbstraction initialized [2023-11-21 22:05:19,623 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 21.11 10:05:17" (1/3) ... [2023-11-21 22:05:19,625 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@29bf2f87 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 21.11 10:05:19, skipping insertion in model container [2023-11-21 22:05:19,625 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.11 10:05:17" (2/3) ... [2023-11-21 22:05:19,627 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@29bf2f87 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 21.11 10:05:19, skipping insertion in model container [2023-11-21 22:05:19,628 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 21.11 10:05:19" (3/3) ... [2023-11-21 22:05:19,631 INFO L112 eAbstractionObserver]: Analyzing ICFG parallel-bakery-4.wvr.c [2023-11-21 22:05:19,655 INFO L203 ceAbstractionStarter]: Automizer settings: Hoare:false NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2023-11-21 22:05:19,656 INFO L162 ceAbstractionStarter]: Applying trace abstraction to program that has 18 error locations. [2023-11-21 22:05:19,656 INFO L514 ceAbstractionStarter]: Constructing petrified ICFG for 1 thread instances. [2023-11-21 22:05:19,750 INFO L144 ThreadInstanceAdder]: Constructed 4 joinOtherThreadTransitions. [2023-11-21 22:05:19,800 INFO L73 FinitePrefix]: Start finitePrefix. Operand has 130 places, 117 transitions, 262 flow [2023-11-21 22:05:19,874 INFO L124 PetriNetUnfolderBase]: 0/113 cut-off events. [2023-11-21 22:05:19,874 INFO L125 PetriNetUnfolderBase]: For 4/4 co-relation queries the response was YES. [2023-11-21 22:05:19,878 INFO L83 FinitePrefix]: Finished finitePrefix Result has 130 conditions, 113 events. 0/113 cut-off events. For 4/4 co-relation queries the response was YES. Maximal size of possible extension queue 7. Compared 280 event pairs, 0 based on Foata normal form. 0/95 useless extension candidates. Maximal degree in co-relation 0. Up to 2 conditions per place. [2023-11-21 22:05:19,879 INFO L82 GeneralOperation]: Start removeDead. Operand has 130 places, 117 transitions, 262 flow [2023-11-21 22:05:19,885 INFO L88 GeneralOperation]: Finished RemoveDead, result has has 125 places, 112 transitions, 248 flow [2023-11-21 22:05:19,898 INFO L356 AbstractCegarLoop]: ======== Iteration 0 == of CEGAR loop == AllErrorsAtOnce ======== [2023-11-21 22:05:19,907 INFO L357 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, mHoare=false, mAutomataTypeConcurrency=PETRI_NET, mHoareTripleChecks=INCREMENTAL, mHoareAnnotationPositions=All, 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;@753d14bf, mLbeIndependenceSettings=[IndependenceType=SEMANTIC, AbstractionType=NONE, UseConditional=false, UseSemiCommutativity=true, Solver=Z3, SolverTimeout=1000ms] [2023-11-21 22:05:19,907 INFO L358 AbstractCegarLoop]: Starting to check reachability of 22 error locations. [2023-11-21 22:05:19,912 INFO L185 PetriNetUnfolderBase]: Found word, exiting Unfolder. [2023-11-21 22:05:19,912 INFO L124 PetriNetUnfolderBase]: 0/2 cut-off events. [2023-11-21 22:05:19,913 INFO L125 PetriNetUnfolderBase]: For 0/0 co-relation queries the response was YES. [2023-11-21 22:05:19,913 INFO L200 CegarLoopForPetriNet]: Found error trace [2023-11-21 22:05:19,914 INFO L208 CegarLoopForPetriNet]: trace histogram [1, 1] [2023-11-21 22:05:19,915 INFO L420 AbstractCegarLoop]: === Iteration 1 === Targeting ULTIMATE.startErr0REQUIRES_VIOLATIONMEMORY_DEREFERENCE === [ULTIMATE.startErr0REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr1REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr2REQUIRES_VIOLATIONMEMORY_DEREFERENCE (and 19 more)] === [2023-11-21 22:05:19,921 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-21 22:05:19,922 INFO L85 PathProgramCache]: Analyzing trace with hash 27739, now seen corresponding path program 1 times [2023-11-21 22:05:19,934 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-21 22:05:19,935 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [2081058104] [2023-11-21 22:05:19,935 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-21 22:05:19,936 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-21 22:05:20,105 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-21 22:05:20,492 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-21 22:05:20,492 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-21 22:05:20,493 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [2081058104] [2023-11-21 22:05:20,493 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [2081058104] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-21 22:05:20,494 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-21 22:05:20,494 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [1] imperfect sequences [] total 1 [2023-11-21 22:05:20,495 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [190127301] [2023-11-21 22:05:20,496 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-21 22:05:20,504 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2023-11-21 22:05:20,508 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-21 22:05:20,535 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2023-11-21 22:05:20,536 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2023-11-21 22:05:20,583 INFO L471 CegarLoopForPetriNet]: Number of universal loopers: 65 out of 117 [2023-11-21 22:05:20,587 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 125 places, 112 transitions, 248 flow. Second operand has 3 states, 3 states have (on average 65.66666666666667) internal successors, (197), 3 states have internal predecessors, (197), 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) [2023-11-21 22:05:20,587 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2023-11-21 22:05:20,587 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 65 of 117 [2023-11-21 22:05:20,588 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2023-11-21 22:05:35,174 INFO L124 PetriNetUnfolderBase]: 69712/107986 cut-off events. [2023-11-21 22:05:35,174 INFO L125 PetriNetUnfolderBase]: For 3207/3207 co-relation queries the response was YES. [2023-11-21 22:05:35,518 INFO L83 FinitePrefix]: Finished finitePrefix Result has 202308 conditions, 107986 events. 69712/107986 cut-off events. For 3207/3207 co-relation queries the response was YES. Maximal size of possible extension queue 3706. Compared 939947 event pairs, 69712 based on Foata normal form. 1/103698 useless extension candidates. Maximal degree in co-relation 192362. Up to 91856 conditions per place. [2023-11-21 22:05:36,665 INFO L140 encePairwiseOnDemand]: 113/117 looper letters, 47 selfloop transitions, 1 changer transitions 0/108 dead transitions. [2023-11-21 22:05:36,666 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 123 places, 108 transitions, 336 flow [2023-11-21 22:05:36,667 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2023-11-21 22:05:36,671 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 3 states. [2023-11-21 22:05:36,683 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 3 states to 3 states and 246 transitions. [2023-11-21 22:05:36,687 INFO L516 CegarLoopForPetriNet]: DFA transition density 0.7008547008547008 [2023-11-21 22:05:36,688 INFO L72 ComplementDD]: Start complementDD. Operand 3 states and 246 transitions. [2023-11-21 22:05:36,689 INFO L73 IsDeterministic]: Start isDeterministic. Operand 3 states and 246 transitions. [2023-11-21 22:05:36,691 INFO L80 IsDeterministic]: Finished isDeterministic. Operand is deterministic. [2023-11-21 22:05:36,694 INFO L117 ReachableStatesCopy]: Start reachableStatesCopy. Operand 3 states and 246 transitions. [2023-11-21 22:05:36,704 INFO L343 DoubleDeckerVisitor]: Before removal of dead ends has 4 states, 3 states have (on average 82.0) internal successors, (246), 3 states have internal predecessors, (246), 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) [2023-11-21 22:05:36,710 INFO L131 ReachableStatesCopy]: Finished reachableStatesCopy Result has 4 states, 4 states have (on average 117.0) internal successors, (468), 4 states have internal predecessors, (468), 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) [2023-11-21 22:05:36,711 INFO L81 ComplementDD]: Finished complementDD. Result has 4 states, 4 states have (on average 117.0) internal successors, (468), 4 states have internal predecessors, (468), 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) [2023-11-21 22:05:36,714 INFO L175 Difference]: Start difference. First operand has 125 places, 112 transitions, 248 flow. Second operand 3 states and 246 transitions. [2023-11-21 22:05:36,715 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 123 places, 108 transitions, 336 flow [2023-11-21 22:05:36,874 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 115 places, 108 transitions, 320 flow, removed 0 selfloop flow, removed 8 redundant places. [2023-11-21 22:05:36,879 INFO L231 Difference]: Finished difference. Result has 115 places, 108 transitions, 226 flow [2023-11-21 22:05:36,882 INFO L264 CegarLoopForPetriNet]: {PETRI_ALPHABET=117, PETRI_DIFFERENCE_MINUEND_FLOW=224, PETRI_DIFFERENCE_MINUEND_PLACES=113, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=108, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=1, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=107, PETRI_DIFFERENCE_SUBTRAHEND_STATES=3, PETRI_FLOW=226, PETRI_PLACES=115, PETRI_TRANSITIONS=108} [2023-11-21 22:05:36,887 INFO L281 CegarLoopForPetriNet]: 125 programPoint places, -10 predicate places. [2023-11-21 22:05:36,888 INFO L495 AbstractCegarLoop]: Abstraction has has 115 places, 108 transitions, 226 flow [2023-11-21 22:05:36,889 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 3 states, 3 states have (on average 65.66666666666667) internal successors, (197), 3 states have internal predecessors, (197), 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) [2023-11-21 22:05:36,889 INFO L200 CegarLoopForPetriNet]: Found error trace [2023-11-21 22:05:36,890 INFO L208 CegarLoopForPetriNet]: trace histogram [1, 1] [2023-11-21 22:05:36,890 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2023-11-21 22:05:36,890 INFO L420 AbstractCegarLoop]: === Iteration 2 === Targeting ULTIMATE.startErr1REQUIRES_VIOLATIONMEMORY_DEREFERENCE === [ULTIMATE.startErr0REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr1REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr2REQUIRES_VIOLATIONMEMORY_DEREFERENCE (and 19 more)] === [2023-11-21 22:05:36,891 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-21 22:05:36,892 INFO L85 PathProgramCache]: Analyzing trace with hash 27740, now seen corresponding path program 1 times [2023-11-21 22:05:36,892 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-21 22:05:36,892 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1677449970] [2023-11-21 22:05:36,893 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-21 22:05:36,893 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-21 22:05:36,950 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-21 22:05:37,227 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-21 22:05:37,228 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-21 22:05:37,228 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1677449970] [2023-11-21 22:05:37,228 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1677449970] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-21 22:05:37,229 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-21 22:05:37,229 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [1] imperfect sequences [] total 1 [2023-11-21 22:05:37,229 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [767742614] [2023-11-21 22:05:37,230 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-21 22:05:37,231 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2023-11-21 22:05:37,231 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-21 22:05:37,232 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2023-11-21 22:05:37,232 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2023-11-21 22:05:37,277 INFO L471 CegarLoopForPetriNet]: Number of universal loopers: 67 out of 117 [2023-11-21 22:05:37,279 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 115 places, 108 transitions, 226 flow. Second operand has 3 states, 3 states have (on average 67.66666666666667) internal successors, (203), 3 states have internal predecessors, (203), 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) [2023-11-21 22:05:37,279 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2023-11-21 22:05:37,279 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 67 of 117 [2023-11-21 22:05:37,279 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2023-11-21 22:05:45,087 INFO L124 PetriNetUnfolderBase]: 46384/74262 cut-off events. [2023-11-21 22:05:45,087 INFO L125 PetriNetUnfolderBase]: For 784/784 co-relation queries the response was YES. [2023-11-21 22:05:45,570 INFO L83 FinitePrefix]: Finished finitePrefix Result has 137052 conditions, 74262 events. 46384/74262 cut-off events. For 784/784 co-relation queries the response was YES. Maximal size of possible extension queue 2544. Compared 645808 event pairs, 46384 based on Foata normal form. 6562/77214 useless extension candidates. Maximal degree in co-relation 137046. Up to 61966 conditions per place. [2023-11-21 22:05:45,944 INFO L140 encePairwiseOnDemand]: 114/117 looper letters, 45 selfloop transitions, 1 changer transitions 0/106 dead transitions. [2023-11-21 22:05:45,944 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 115 places, 106 transitions, 314 flow [2023-11-21 22:05:45,945 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2023-11-21 22:05:45,945 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 3 states. [2023-11-21 22:05:45,951 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 3 states to 3 states and 249 transitions. [2023-11-21 22:05:45,952 INFO L516 CegarLoopForPetriNet]: DFA transition density 0.7094017094017094 [2023-11-21 22:05:45,953 INFO L72 ComplementDD]: Start complementDD. Operand 3 states and 249 transitions. [2023-11-21 22:05:45,953 INFO L73 IsDeterministic]: Start isDeterministic. Operand 3 states and 249 transitions. [2023-11-21 22:05:45,953 INFO L80 IsDeterministic]: Finished isDeterministic. Operand is deterministic. [2023-11-21 22:05:45,954 INFO L117 ReachableStatesCopy]: Start reachableStatesCopy. Operand 3 states and 249 transitions. [2023-11-21 22:05:45,957 INFO L343 DoubleDeckerVisitor]: Before removal of dead ends has 4 states, 3 states have (on average 83.0) internal successors, (249), 3 states have internal predecessors, (249), 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) [2023-11-21 22:05:45,961 INFO L131 ReachableStatesCopy]: Finished reachableStatesCopy Result has 4 states, 4 states have (on average 117.0) internal successors, (468), 4 states have internal predecessors, (468), 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) [2023-11-21 22:05:45,961 INFO L81 ComplementDD]: Finished complementDD. Result has 4 states, 4 states have (on average 117.0) internal successors, (468), 4 states have internal predecessors, (468), 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) [2023-11-21 22:05:45,962 INFO L175 Difference]: Start difference. First operand has 115 places, 108 transitions, 226 flow. Second operand 3 states and 249 transitions. [2023-11-21 22:05:45,962 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 115 places, 106 transitions, 314 flow [2023-11-21 22:05:45,965 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 114 places, 106 transitions, 313 flow, removed 0 selfloop flow, removed 1 redundant places. [2023-11-21 22:05:45,968 INFO L231 Difference]: Finished difference. Result has 114 places, 106 transitions, 223 flow [2023-11-21 22:05:45,969 INFO L264 CegarLoopForPetriNet]: {PETRI_ALPHABET=117, PETRI_DIFFERENCE_MINUEND_FLOW=221, PETRI_DIFFERENCE_MINUEND_PLACES=112, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=106, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=1, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=105, PETRI_DIFFERENCE_SUBTRAHEND_STATES=3, PETRI_FLOW=223, PETRI_PLACES=114, PETRI_TRANSITIONS=106} [2023-11-21 22:05:45,971 INFO L281 CegarLoopForPetriNet]: 125 programPoint places, -11 predicate places. [2023-11-21 22:05:45,972 INFO L495 AbstractCegarLoop]: Abstraction has has 114 places, 106 transitions, 223 flow [2023-11-21 22:05:45,976 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 3 states, 3 states have (on average 67.66666666666667) internal successors, (203), 3 states have internal predecessors, (203), 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) [2023-11-21 22:05:45,977 INFO L200 CegarLoopForPetriNet]: Found error trace [2023-11-21 22:05:45,977 INFO L208 CegarLoopForPetriNet]: trace histogram [1, 1, 1, 1, 1] [2023-11-21 22:05:45,977 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2023-11-21 22:05:45,979 INFO L420 AbstractCegarLoop]: === Iteration 3 === Targeting ULTIMATE.startErr2REQUIRES_VIOLATIONMEMORY_DEREFERENCE === [ULTIMATE.startErr0REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr1REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr2REQUIRES_VIOLATIONMEMORY_DEREFERENCE (and 19 more)] === [2023-11-21 22:05:45,982 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-21 22:05:45,983 INFO L85 PathProgramCache]: Analyzing trace with hash 827327823, now seen corresponding path program 1 times [2023-11-21 22:05:45,984 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-21 22:05:45,992 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [736596882] [2023-11-21 22:05:45,999 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-21 22:05:46,001 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-21 22:05:46,046 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-21 22:05:46,196 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-21 22:05:46,196 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-21 22:05:46,197 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [736596882] [2023-11-21 22:05:46,197 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [736596882] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-21 22:05:46,198 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-21 22:05:46,198 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [1] imperfect sequences [] total 1 [2023-11-21 22:05:46,199 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [400031137] [2023-11-21 22:05:46,200 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-21 22:05:46,201 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2023-11-21 22:05:46,201 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-21 22:05:46,202 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2023-11-21 22:05:46,202 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2023-11-21 22:05:46,242 INFO L471 CegarLoopForPetriNet]: Number of universal loopers: 65 out of 117 [2023-11-21 22:05:46,243 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 114 places, 106 transitions, 223 flow. Second operand has 3 states, 3 states have (on average 66.33333333333333) internal successors, (199), 3 states have internal predecessors, (199), 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) [2023-11-21 22:05:46,243 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2023-11-21 22:05:46,243 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 65 of 117 [2023-11-21 22:05:46,244 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2023-11-21 22:05:53,807 INFO L124 PetriNetUnfolderBase]: 48336/75491 cut-off events. [2023-11-21 22:05:53,808 INFO L125 PetriNetUnfolderBase]: For 703/703 co-relation queries the response was YES. [2023-11-21 22:05:53,916 INFO L83 FinitePrefix]: Finished finitePrefix Result has 140972 conditions, 75491 events. 48336/75491 cut-off events. For 703/703 co-relation queries the response was YES. Maximal size of possible extension queue 2571. Compared 637894 event pairs, 48336 based on Foata normal form. 0/73344 useless extension candidates. Maximal degree in co-relation 140965. Up to 64656 conditions per place. [2023-11-21 22:05:54,220 INFO L140 encePairwiseOnDemand]: 114/117 looper letters, 47 selfloop transitions, 1 changer transitions 0/104 dead transitions. [2023-11-21 22:05:54,221 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 114 places, 104 transitions, 315 flow [2023-11-21 22:05:54,221 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2023-11-21 22:05:54,236 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 3 states. [2023-11-21 22:05:54,238 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 3 states to 3 states and 245 transitions. [2023-11-21 22:05:54,238 INFO L516 CegarLoopForPetriNet]: DFA transition density 0.698005698005698 [2023-11-21 22:05:54,238 INFO L72 ComplementDD]: Start complementDD. Operand 3 states and 245 transitions. [2023-11-21 22:05:54,251 INFO L73 IsDeterministic]: Start isDeterministic. Operand 3 states and 245 transitions. [2023-11-21 22:05:54,251 INFO L80 IsDeterministic]: Finished isDeterministic. Operand is deterministic. [2023-11-21 22:05:54,251 INFO L117 ReachableStatesCopy]: Start reachableStatesCopy. Operand 3 states and 245 transitions. [2023-11-21 22:05:54,253 INFO L343 DoubleDeckerVisitor]: Before removal of dead ends has 4 states, 3 states have (on average 81.66666666666667) internal successors, (245), 3 states have internal predecessors, (245), 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) [2023-11-21 22:05:54,256 INFO L131 ReachableStatesCopy]: Finished reachableStatesCopy Result has 4 states, 4 states have (on average 117.0) internal successors, (468), 4 states have internal predecessors, (468), 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) [2023-11-21 22:05:54,257 INFO L81 ComplementDD]: Finished complementDD. Result has 4 states, 4 states have (on average 117.0) internal successors, (468), 4 states have internal predecessors, (468), 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) [2023-11-21 22:05:54,257 INFO L175 Difference]: Start difference. First operand has 114 places, 106 transitions, 223 flow. Second operand 3 states and 245 transitions. [2023-11-21 22:05:54,258 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 114 places, 104 transitions, 315 flow [2023-11-21 22:05:54,261 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 113 places, 104 transitions, 314 flow, removed 0 selfloop flow, removed 1 redundant places. [2023-11-21 22:05:54,265 INFO L231 Difference]: Finished difference. Result has 113 places, 104 transitions, 220 flow [2023-11-21 22:05:54,266 INFO L264 CegarLoopForPetriNet]: {PETRI_ALPHABET=117, PETRI_DIFFERENCE_MINUEND_FLOW=218, PETRI_DIFFERENCE_MINUEND_PLACES=111, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=104, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=1, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=103, PETRI_DIFFERENCE_SUBTRAHEND_STATES=3, PETRI_FLOW=220, PETRI_PLACES=113, PETRI_TRANSITIONS=104} [2023-11-21 22:05:54,267 INFO L281 CegarLoopForPetriNet]: 125 programPoint places, -12 predicate places. [2023-11-21 22:05:54,268 INFO L495 AbstractCegarLoop]: Abstraction has has 113 places, 104 transitions, 220 flow [2023-11-21 22:05:54,268 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 3 states, 3 states have (on average 66.33333333333333) internal successors, (199), 3 states have internal predecessors, (199), 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) [2023-11-21 22:05:54,268 INFO L200 CegarLoopForPetriNet]: Found error trace [2023-11-21 22:05:54,269 INFO L208 CegarLoopForPetriNet]: trace histogram [1, 1, 1, 1, 1] [2023-11-21 22:05:54,269 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable2 [2023-11-21 22:05:54,269 INFO L420 AbstractCegarLoop]: === Iteration 4 === Targeting ULTIMATE.startErr3REQUIRES_VIOLATIONMEMORY_DEREFERENCE === [ULTIMATE.startErr0REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr1REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr2REQUIRES_VIOLATIONMEMORY_DEREFERENCE (and 19 more)] === [2023-11-21 22:05:54,270 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-21 22:05:54,270 INFO L85 PathProgramCache]: Analyzing trace with hash 827327824, now seen corresponding path program 1 times [2023-11-21 22:05:54,270 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-21 22:05:54,271 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [676580766] [2023-11-21 22:05:54,271 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-21 22:05:54,271 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-21 22:05:54,298 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-21 22:05:54,455 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-21 22:05:54,455 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-21 22:05:54,455 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [676580766] [2023-11-21 22:05:54,456 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [676580766] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-21 22:05:54,456 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-21 22:05:54,456 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [1] imperfect sequences [] total 1 [2023-11-21 22:05:54,457 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [2112489220] [2023-11-21 22:05:54,457 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-21 22:05:54,457 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2023-11-21 22:05:54,457 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-21 22:05:54,459 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2023-11-21 22:05:54,460 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2023-11-21 22:05:54,501 INFO L471 CegarLoopForPetriNet]: Number of universal loopers: 65 out of 117 [2023-11-21 22:05:54,502 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 113 places, 104 transitions, 220 flow. Second operand has 3 states, 3 states have (on average 66.33333333333333) internal successors, (199), 3 states have internal predecessors, (199), 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) [2023-11-21 22:05:54,502 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2023-11-21 22:05:54,502 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 65 of 117 [2023-11-21 22:05:54,502 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand [2023-11-21 22:06:01,832 INFO L124 PetriNetUnfolderBase]: 48336/74759 cut-off events. [2023-11-21 22:06:01,832 INFO L125 PetriNetUnfolderBase]: For 703/703 co-relation queries the response was YES. [2023-11-21 22:06:01,949 INFO L83 FinitePrefix]: Finished finitePrefix Result has 140241 conditions, 74759 events. 48336/74759 cut-off events. For 703/703 co-relation queries the response was YES. Maximal size of possible extension queue 2564. Compared 623531 event pairs, 48336 based on Foata normal form. 0/72612 useless extension candidates. Maximal degree in co-relation 140233. Up to 64656 conditions per place. [2023-11-21 22:06:02,205 INFO L140 encePairwiseOnDemand]: 114/117 looper letters, 47 selfloop transitions, 1 changer transitions 0/102 dead transitions. [2023-11-21 22:06:02,205 INFO L145 encePairwiseOnDemand]: Finished differencePairwiseOnDemand. Result has 113 places, 102 transitions, 312 flow [2023-11-21 22:06:02,205 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2023-11-21 22:06:02,205 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 3 states. [2023-11-21 22:06:02,206 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 3 states to 3 states and 245 transitions. [2023-11-21 22:06:02,207 INFO L516 CegarLoopForPetriNet]: DFA transition density 0.698005698005698 [2023-11-21 22:06:02,207 INFO L72 ComplementDD]: Start complementDD. Operand 3 states and 245 transitions. [2023-11-21 22:06:02,207 INFO L73 IsDeterministic]: Start isDeterministic. Operand 3 states and 245 transitions. [2023-11-21 22:06:02,208 INFO L80 IsDeterministic]: Finished isDeterministic. Operand is deterministic. [2023-11-21 22:06:02,208 INFO L117 ReachableStatesCopy]: Start reachableStatesCopy. Operand 3 states and 245 transitions. [2023-11-21 22:06:02,209 INFO L343 DoubleDeckerVisitor]: Before removal of dead ends has 4 states, 3 states have (on average 81.66666666666667) internal successors, (245), 3 states have internal predecessors, (245), 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) [2023-11-21 22:06:02,210 INFO L131 ReachableStatesCopy]: Finished reachableStatesCopy Result has 4 states, 4 states have (on average 117.0) internal successors, (468), 4 states have internal predecessors, (468), 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) [2023-11-21 22:06:02,211 INFO L81 ComplementDD]: Finished complementDD. Result has 4 states, 4 states have (on average 117.0) internal successors, (468), 4 states have internal predecessors, (468), 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) [2023-11-21 22:06:02,211 INFO L175 Difference]: Start difference. First operand has 113 places, 104 transitions, 220 flow. Second operand 3 states and 245 transitions. [2023-11-21 22:06:02,211 INFO L82 GeneralOperation]: Start removeRedundantFlow. Operand has 113 places, 102 transitions, 312 flow [2023-11-21 22:06:02,213 INFO L88 GeneralOperation]: Finished removeRedundantFlow, result has has 112 places, 102 transitions, 311 flow, removed 0 selfloop flow, removed 1 redundant places. [2023-11-21 22:06:02,215 INFO L231 Difference]: Finished difference. Result has 112 places, 102 transitions, 217 flow [2023-11-21 22:06:02,215 INFO L264 CegarLoopForPetriNet]: {PETRI_ALPHABET=117, PETRI_DIFFERENCE_MINUEND_FLOW=215, PETRI_DIFFERENCE_MINUEND_PLACES=110, PETRI_DIFFERENCE_MINUEND_TRANSITIONS=102, PETRI_DIFFERENCE_SUBTRAHEND_LETTERS_WITH_MORE_CHANGERS_THAN_LOOPERS=1, PETRI_DIFFERENCE_SUBTRAHEND_LOOPER_ONLY_LETTERS=101, PETRI_DIFFERENCE_SUBTRAHEND_STATES=3, PETRI_FLOW=217, PETRI_PLACES=112, PETRI_TRANSITIONS=102} [2023-11-21 22:06:02,216 INFO L281 CegarLoopForPetriNet]: 125 programPoint places, -13 predicate places. [2023-11-21 22:06:02,216 INFO L495 AbstractCegarLoop]: Abstraction has has 112 places, 102 transitions, 217 flow [2023-11-21 22:06:02,217 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 3 states, 3 states have (on average 66.33333333333333) internal successors, (199), 3 states have internal predecessors, (199), 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) [2023-11-21 22:06:02,217 INFO L200 CegarLoopForPetriNet]: Found error trace [2023-11-21 22:06:02,217 INFO L208 CegarLoopForPetriNet]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1] [2023-11-21 22:06:02,217 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3 [2023-11-21 22:06:02,218 INFO L420 AbstractCegarLoop]: === Iteration 5 === Targeting ULTIMATE.startErr4REQUIRES_VIOLATIONMEMORY_DEREFERENCE === [ULTIMATE.startErr0REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr1REQUIRES_VIOLATIONMEMORY_DEREFERENCE, ULTIMATE.startErr2REQUIRES_VIOLATIONMEMORY_DEREFERENCE (and 19 more)] === [2023-11-21 22:06:02,218 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-21 22:06:02,218 INFO L85 PathProgramCache]: Analyzing trace with hash -1893177183, now seen corresponding path program 1 times [2023-11-21 22:06:02,218 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-21 22:06:02,219 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1127579786] [2023-11-21 22:06:02,219 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-21 22:06:02,219 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-21 22:06:02,235 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-21 22:06:02,290 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2023-11-21 22:06:02,291 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-21 22:06:02,291 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1127579786] [2023-11-21 22:06:02,291 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1127579786] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-21 22:06:02,292 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-21 22:06:02,292 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [1] imperfect sequences [] total 1 [2023-11-21 22:06:02,292 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [2050661400] [2023-11-21 22:06:02,292 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-21 22:06:02,293 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2023-11-21 22:06:02,293 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-21 22:06:02,294 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2023-11-21 22:06:02,294 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2023-11-21 22:06:02,330 INFO L471 CegarLoopForPetriNet]: Number of universal loopers: 65 out of 117 [2023-11-21 22:06:02,330 INFO L103 encePairwiseOnDemand]: Start differencePairwiseOnDemand. First operand has 112 places, 102 transitions, 217 flow. Second operand has 3 states, 3 states have (on average 67.0) internal successors, (201), 3 states have internal predecessors, (201), 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) [2023-11-21 22:06:02,331 INFO L112 encePairwiseOnDemand]: Universal subtrahend loopers provided by user. [2023-11-21 22:06:02,331 INFO L113 encePairwiseOnDemand]: Number of universal subtrahend loopers: 65 of 117 [2023-11-21 22:06:02,331 INFO L73 FinitePrefix]: Start finitePrefix. Operand will be constructed on-demand