./Ultimate.py --spec ../../sv-benchmarks/c/ReachSafety.prp --file ../../sv-benchmarks/c/loop-invgen/apache-get-tag_true-unreach-call_true-termination.i --full-output --architecture 32bit -------------------------------------------------------------------------------- Checking for ERROR reachability Using default analysis Version 5842f4b8 Calling Ultimate with: java -Dosgi.configuration.area=/tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/data/config -Xmx12G -Xms1G -jar /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -data @noDefault -ultimatedata /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/data -tc /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/config/AutomizerReach.xml -i ../../sv-benchmarks/c/loop-invgen/apache-get-tag_true-unreach-call_true-termination.i -s /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/config/svcomp-Reach-32bit-PetriAutomizer_Default.epf --cacsl2boogietranslator.entry.function main --witnessprinter.witness.directory /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer --witnessprinter.witness.filename witness.graphml --witnessprinter.write.witness.besides.input.file false --witnessprinter.graph.data.specification CHECK( init(main()), LTL(G ! call(__VERIFIER_error())) ) --witnessprinter.graph.data.producer Automizer --witnessprinter.graph.data.architecture 32bit --witnessprinter.graph.data.programhash 01c80fcdd0a0da14cc25a34188deb5573e4a4209 ........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... Execution finished normally Writing output log to file Ultimate.log Result: TRUE --- Real Ultimate output --- This is Ultimate 0.1.23-5842f4b [2018-11-18 15:44:49,464 INFO L170 SettingsManager]: Resetting all preferences to default values... [2018-11-18 15:44:49,465 INFO L174 SettingsManager]: Resetting UltimateCore preferences to default values [2018-11-18 15:44:49,473 INFO L177 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2018-11-18 15:44:49,473 INFO L174 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2018-11-18 15:44:49,474 INFO L174 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2018-11-18 15:44:49,475 INFO L174 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2018-11-18 15:44:49,476 INFO L174 SettingsManager]: Resetting LassoRanker preferences to default values [2018-11-18 15:44:49,477 INFO L174 SettingsManager]: Resetting Reaching Definitions preferences to default values [2018-11-18 15:44:49,478 INFO L174 SettingsManager]: Resetting SyntaxChecker preferences to default values [2018-11-18 15:44:49,478 INFO L177 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2018-11-18 15:44:49,478 INFO L174 SettingsManager]: Resetting LTL2Aut preferences to default values [2018-11-18 15:44:49,479 INFO L174 SettingsManager]: Resetting PEA to Boogie preferences to default values [2018-11-18 15:44:49,480 INFO L174 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2018-11-18 15:44:49,480 INFO L174 SettingsManager]: Resetting ChcToBoogie preferences to default values [2018-11-18 15:44:49,481 INFO L174 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2018-11-18 15:44:49,481 INFO L174 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2018-11-18 15:44:49,482 INFO L174 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2018-11-18 15:44:49,484 INFO L174 SettingsManager]: Resetting CodeCheck preferences to default values [2018-11-18 15:44:49,484 INFO L174 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2018-11-18 15:44:49,485 INFO L174 SettingsManager]: Resetting RCFGBuilder preferences to default values [2018-11-18 15:44:49,486 INFO L174 SettingsManager]: Resetting TraceAbstraction preferences to default values [2018-11-18 15:44:49,488 INFO L177 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... [2018-11-18 15:44:49,488 INFO L177 SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring... [2018-11-18 15:44:49,488 INFO L174 SettingsManager]: Resetting TreeAutomizer preferences to default values [2018-11-18 15:44:49,489 INFO L174 SettingsManager]: Resetting IcfgTransformer preferences to default values [2018-11-18 15:44:49,489 INFO L174 SettingsManager]: Resetting Boogie Printer preferences to default values [2018-11-18 15:44:49,490 INFO L174 SettingsManager]: Resetting ReqPrinter preferences to default values [2018-11-18 15:44:49,490 INFO L174 SettingsManager]: Resetting Witness Printer preferences to default values [2018-11-18 15:44:49,491 INFO L177 SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring... [2018-11-18 15:44:49,491 INFO L174 SettingsManager]: Resetting CDTParser preferences to default values [2018-11-18 15:44:49,492 INFO L177 SettingsManager]: AutomataScriptParser provides no preferences, ignoring... [2018-11-18 15:44:49,492 INFO L177 SettingsManager]: ReqParser provides no preferences, ignoring... [2018-11-18 15:44:49,492 INFO L174 SettingsManager]: Resetting SmtParser preferences to default values [2018-11-18 15:44:49,492 INFO L174 SettingsManager]: Resetting Witness Parser preferences to default values [2018-11-18 15:44:49,493 INFO L181 SettingsManager]: Finished resetting all preferences to default values... [2018-11-18 15:44:49,493 INFO L98 SettingsManager]: Beginning loading settings from /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/config/svcomp-Reach-32bit-PetriAutomizer_Default.epf [2018-11-18 15:44:49,502 INFO L110 SettingsManager]: Loading preferences was successful [2018-11-18 15:44:49,502 INFO L112 SettingsManager]: Preferences different from defaults after loading the file: [2018-11-18 15:44:49,503 INFO L131 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2018-11-18 15:44:49,503 INFO L133 SettingsManager]: * Process only entry and re-entry procedures=false [2018-11-18 15:44:49,504 INFO L131 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2018-11-18 15:44:49,504 INFO L133 SettingsManager]: * Create parallel compositions if possible=false [2018-11-18 15:44:49,504 INFO L133 SettingsManager]: * Use SBE=true [2018-11-18 15:44:49,504 INFO L131 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2018-11-18 15:44:49,504 INFO L133 SettingsManager]: * sizeof long=4 [2018-11-18 15:44:49,504 INFO L133 SettingsManager]: * Overapproximate operations on floating types=true [2018-11-18 15:44:49,504 INFO L133 SettingsManager]: * sizeof POINTER=4 [2018-11-18 15:44:49,504 INFO L133 SettingsManager]: * Check division by zero=IGNORE [2018-11-18 15:44:49,505 INFO L133 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2018-11-18 15:44:49,505 INFO L133 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2018-11-18 15:44:49,505 INFO L133 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2018-11-18 15:44:49,505 INFO L133 SettingsManager]: * sizeof long double=12 [2018-11-18 15:44:49,505 INFO L133 SettingsManager]: * Check if freed pointer was valid=false [2018-11-18 15:44:49,505 INFO L133 SettingsManager]: * Use constant arrays=true [2018-11-18 15:44:49,505 INFO L133 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2018-11-18 15:44:49,505 INFO L131 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2018-11-18 15:44:49,506 INFO L133 SettingsManager]: * Size of a code block=SequenceOfStatements [2018-11-18 15:44:49,506 INFO L133 SettingsManager]: * To the following directory=./dump/ [2018-11-18 15:44:49,506 INFO L133 SettingsManager]: * SMT solver=External_DefaultMode [2018-11-18 15:44:49,506 INFO L133 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2018-11-18 15:44:49,506 INFO L131 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2018-11-18 15:44:49,506 INFO L133 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2018-11-18 15:44:49,506 INFO L133 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2018-11-18 15:44:49,506 INFO L133 SettingsManager]: * Trace refinement strategy=CAMEL [2018-11-18 15:44:49,507 INFO L133 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2018-11-18 15:44:49,507 INFO L133 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2018-11-18 15:44:49,507 INFO L133 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true 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-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness filename -> witness.graphml 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 ! call(__VERIFIER_error())) ) 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 -> 01c80fcdd0a0da14cc25a34188deb5573e4a4209 [2018-11-18 15:44:49,529 INFO L81 nceAwareModelManager]: Repository-Root is: /tmp [2018-11-18 15:44:49,538 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2018-11-18 15:44:49,541 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2018-11-18 15:44:49,542 INFO L271 PluginConnector]: Initializing CDTParser... [2018-11-18 15:44:49,542 INFO L276 PluginConnector]: CDTParser initialized [2018-11-18 15:44:49,543 INFO L418 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/../../sv-benchmarks/c/loop-invgen/apache-get-tag_true-unreach-call_true-termination.i [2018-11-18 15:44:49,585 INFO L221 CDTParser]: Created temporary CDT project at /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/data/8e54d66fa/a2d76fe046454d16831c1bbe14ec0925/FLAG5fa8777d5 [2018-11-18 15:44:49,924 INFO L307 CDTParser]: Found 1 translation units. [2018-11-18 15:44:49,925 INFO L161 CDTParser]: Scanning /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/sv-benchmarks/c/loop-invgen/apache-get-tag_true-unreach-call_true-termination.i [2018-11-18 15:44:49,930 INFO L355 CDTParser]: About to delete temporary CDT project at /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/data/8e54d66fa/a2d76fe046454d16831c1bbe14ec0925/FLAG5fa8777d5 [2018-11-18 15:44:50,341 INFO L363 CDTParser]: Successfully deleted /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/data/8e54d66fa/a2d76fe046454d16831c1bbe14ec0925 [2018-11-18 15:44:50,343 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2018-11-18 15:44:50,344 INFO L131 ToolchainWalker]: Walking toolchain with 5 elements. [2018-11-18 15:44:50,344 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2018-11-18 15:44:50,344 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2018-11-18 15:44:50,347 INFO L276 PluginConnector]: CACSL2BoogieTranslator initialized [2018-11-18 15:44:50,348 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,350 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@497aa5de and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50, skipping insertion in model container [2018-11-18 15:44:50,350 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,355 INFO L145 MainTranslator]: Starting translation in SV-COMP mode [2018-11-18 15:44:50,374 INFO L176 MainTranslator]: Built tables and reachable declarations [2018-11-18 15:44:50,487 INFO L201 PostProcessor]: Analyzing one entry point: main [2018-11-18 15:44:50,489 INFO L191 MainTranslator]: Completed pre-run [2018-11-18 15:44:50,501 INFO L201 PostProcessor]: Analyzing one entry point: main [2018-11-18 15:44:50,508 INFO L195 MainTranslator]: Completed translation [2018-11-18 15:44:50,508 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50 WrapperNode [2018-11-18 15:44:50,508 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2018-11-18 15:44:50,509 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2018-11-18 15:44:50,509 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2018-11-18 15:44:50,509 INFO L276 PluginConnector]: Boogie Preprocessor initialized [2018-11-18 15:44:50,516 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,516 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,519 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,520 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,522 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,525 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,526 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (1/1) ... [2018-11-18 15:44:50,527 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2018-11-18 15:44:50,527 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2018-11-18 15:44:50,527 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2018-11-18 15:44:50,527 INFO L276 PluginConnector]: RCFGBuilder initialized [2018-11-18 15:44:50,528 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (1/1) ... No working directory specified, using /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/z3 Starting monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2018-11-18 15:44:50,597 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2018-11-18 15:44:50,597 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2018-11-18 15:44:50,597 INFO L138 BoogieDeclarations]: Found implementation of procedure __VERIFIER_assert [2018-11-18 15:44:50,597 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2018-11-18 15:44:50,597 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_error [2018-11-18 15:44:50,597 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_assume [2018-11-18 15:44:50,598 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_assert [2018-11-18 15:44:50,598 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_int [2018-11-18 15:44:50,598 INFO L130 BoogieDeclarations]: Found specification of procedure main [2018-11-18 15:44:50,598 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2018-11-18 15:44:50,598 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2018-11-18 15:44:50,732 INFO L278 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2018-11-18 15:44:50,733 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 18.11 03:44:50 BoogieIcfgContainer [2018-11-18 15:44:50,733 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2018-11-18 15:44:50,733 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2018-11-18 15:44:50,733 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2018-11-18 15:44:50,736 INFO L276 PluginConnector]: TraceAbstraction initialized [2018-11-18 15:44:50,736 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 18.11 03:44:50" (1/3) ... [2018-11-18 15:44:50,736 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@4f24cf4f and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 18.11 03:44:50, skipping insertion in model container [2018-11-18 15:44:50,737 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 18.11 03:44:50" (2/3) ... [2018-11-18 15:44:50,737 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@4f24cf4f and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 18.11 03:44:50, skipping insertion in model container [2018-11-18 15:44:50,737 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 18.11 03:44:50" (3/3) ... [2018-11-18 15:44:50,738 INFO L112 eAbstractionObserver]: Analyzing ICFG apache-get-tag_true-unreach-call_true-termination.i [2018-11-18 15:44:50,743 INFO L136 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2018-11-18 15:44:50,747 INFO L148 ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations. [2018-11-18 15:44:50,755 INFO L257 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2018-11-18 15:44:50,772 INFO L133 ementStrategyFactory]: Using default assertion order modulation [2018-11-18 15:44:50,772 INFO L382 AbstractCegarLoop]: Interprodecural is true [2018-11-18 15:44:50,773 INFO L383 AbstractCegarLoop]: Hoare is true [2018-11-18 15:44:50,773 INFO L384 AbstractCegarLoop]: Compute interpolants for FPandBP [2018-11-18 15:44:50,773 INFO L385 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2018-11-18 15:44:50,773 INFO L386 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2018-11-18 15:44:50,773 INFO L387 AbstractCegarLoop]: Difference is false [2018-11-18 15:44:50,773 INFO L388 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2018-11-18 15:44:50,773 INFO L393 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2018-11-18 15:44:50,785 INFO L276 IsEmpty]: Start isEmpty. Operand 49 states. [2018-11-18 15:44:50,789 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 13 [2018-11-18 15:44:50,789 INFO L367 BasicCegarLoop]: Found error trace [2018-11-18 15:44:50,789 INFO L375 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-11-18 15:44:50,791 INFO L423 AbstractCegarLoop]: === Iteration 1 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2018-11-18 15:44:50,796 INFO L141 PredicateUnifier]: Initialized classic predicate unifier [2018-11-18 15:44:50,796 INFO L82 PathProgramCache]: Analyzing trace with hash -1656305570, now seen corresponding path program 1 times [2018-11-18 15:44:50,797 INFO L223 ckRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-11-18 15:44:50,798 INFO L69 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-11-18 15:44:50,827 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:50,828 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-11-18 15:44:50,828 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:50,853 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-11-18 15:44:50,870 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-11-18 15:44:50,871 INFO L312 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-11-18 15:44:50,871 INFO L327 seRefinementStrategy]: Number of different interpolants: perfect sequences [2] imperfect sequences [] total 2 [2018-11-18 15:44:50,874 INFO L459 AbstractCegarLoop]: Interpolant automaton has 2 states [2018-11-18 15:44:50,881 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 2 interpolants. [2018-11-18 15:44:50,881 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2018-11-18 15:44:50,883 INFO L87 Difference]: Start difference. First operand 49 states. Second operand 2 states. [2018-11-18 15:44:50,903 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-11-18 15:44:50,904 INFO L93 Difference]: Finished difference Result 91 states and 160 transitions. [2018-11-18 15:44:50,904 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 2 states. [2018-11-18 15:44:50,905 INFO L78 Accepts]: Start accepts. Automaton has 2 states. Word has length 12 [2018-11-18 15:44:50,905 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-11-18 15:44:50,912 INFO L225 Difference]: With dead ends: 91 [2018-11-18 15:44:50,912 INFO L226 Difference]: Without dead ends: 44 [2018-11-18 15:44:50,915 INFO L604 BasicCegarLoop]: 0 DeclaredPredicates, 2 GetRequests, 2 SyntacticMatches, 0 SemanticMatches, 0 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2018-11-18 15:44:50,926 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 44 states. [2018-11-18 15:44:50,943 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 44 to 44. [2018-11-18 15:44:50,944 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 44 states. [2018-11-18 15:44:50,945 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 44 states to 44 states and 62 transitions. [2018-11-18 15:44:50,946 INFO L78 Accepts]: Start accepts. Automaton has 44 states and 62 transitions. Word has length 12 [2018-11-18 15:44:50,946 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-11-18 15:44:50,946 INFO L480 AbstractCegarLoop]: Abstraction has 44 states and 62 transitions. [2018-11-18 15:44:50,946 INFO L481 AbstractCegarLoop]: Interpolant automaton has 2 states. [2018-11-18 15:44:50,946 INFO L276 IsEmpty]: Start isEmpty. Operand 44 states and 62 transitions. [2018-11-18 15:44:50,947 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 15 [2018-11-18 15:44:50,947 INFO L367 BasicCegarLoop]: Found error trace [2018-11-18 15:44:50,947 INFO L375 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-11-18 15:44:50,947 INFO L423 AbstractCegarLoop]: === Iteration 2 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2018-11-18 15:44:50,947 INFO L141 PredicateUnifier]: Initialized classic predicate unifier [2018-11-18 15:44:50,947 INFO L82 PathProgramCache]: Analyzing trace with hash -145433870, now seen corresponding path program 1 times [2018-11-18 15:44:50,947 INFO L223 ckRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-11-18 15:44:50,947 INFO L69 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-11-18 15:44:50,948 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:50,948 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-11-18 15:44:50,948 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:50,958 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-11-18 15:44:51,010 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-11-18 15:44:51,010 INFO L312 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-11-18 15:44:51,011 INFO L327 seRefinementStrategy]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2018-11-18 15:44:51,012 INFO L459 AbstractCegarLoop]: Interpolant automaton has 5 states [2018-11-18 15:44:51,012 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2018-11-18 15:44:51,012 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2018-11-18 15:44:51,012 INFO L87 Difference]: Start difference. First operand 44 states and 62 transitions. Second operand 5 states. [2018-11-18 15:44:51,137 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-11-18 15:44:51,137 INFO L93 Difference]: Finished difference Result 50 states and 67 transitions. [2018-11-18 15:44:51,137 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2018-11-18 15:44:51,138 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 14 [2018-11-18 15:44:51,138 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-11-18 15:44:51,138 INFO L225 Difference]: With dead ends: 50 [2018-11-18 15:44:51,138 INFO L226 Difference]: Without dead ends: 48 [2018-11-18 15:44:51,139 INFO L604 BasicCegarLoop]: 0 DeclaredPredicates, 6 GetRequests, 2 SyntacticMatches, 0 SemanticMatches, 4 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=11, Invalid=19, Unknown=0, NotChecked=0, Total=30 [2018-11-18 15:44:51,139 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 48 states. [2018-11-18 15:44:51,148 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 48 to 48. [2018-11-18 15:44:51,148 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 48 states. [2018-11-18 15:44:51,149 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 48 states to 48 states and 65 transitions. [2018-11-18 15:44:51,149 INFO L78 Accepts]: Start accepts. Automaton has 48 states and 65 transitions. Word has length 14 [2018-11-18 15:44:51,149 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-11-18 15:44:51,149 INFO L480 AbstractCegarLoop]: Abstraction has 48 states and 65 transitions. [2018-11-18 15:44:51,149 INFO L481 AbstractCegarLoop]: Interpolant automaton has 5 states. [2018-11-18 15:44:51,150 INFO L276 IsEmpty]: Start isEmpty. Operand 48 states and 65 transitions. [2018-11-18 15:44:51,150 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 20 [2018-11-18 15:44:51,150 INFO L367 BasicCegarLoop]: Found error trace [2018-11-18 15:44:51,150 INFO L375 BasicCegarLoop]: trace histogram [2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-11-18 15:44:51,151 INFO L423 AbstractCegarLoop]: === Iteration 3 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2018-11-18 15:44:51,151 INFO L141 PredicateUnifier]: Initialized classic predicate unifier [2018-11-18 15:44:51,151 INFO L82 PathProgramCache]: Analyzing trace with hash 840682065, now seen corresponding path program 1 times [2018-11-18 15:44:51,151 INFO L223 ckRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-11-18 15:44:51,151 INFO L69 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-11-18 15:44:51,152 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:51,152 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-11-18 15:44:51,152 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:51,158 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-11-18 15:44:51,224 INFO L134 CoverageAnalysis]: Checked inductivity of 2 backedges. 1 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-11-18 15:44:51,224 INFO L300 seRefinementStrategy]: The current sequences of interpolants are not accepted, trying to find more. [2018-11-18 15:44:51,224 INFO L223 ckRefinementStrategy]: Switched to mode Z3_FP No working directory specified, using /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/z3 Starting monitored process 2 with z3 -smt2 -in SMTLIB2_COMPLIANT=true -t:12000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 2 with z3 -smt2 -in SMTLIB2_COMPLIANT=true -t:12000 [2018-11-18 15:44:51,238 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-11-18 15:44:51,247 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-11-18 15:44:51,251 INFO L273 TraceCheckSpWp]: Computing forward predicates... [2018-11-18 15:44:51,301 INFO L134 CoverageAnalysis]: Checked inductivity of 2 backedges. 2 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-11-18 15:44:51,318 INFO L312 seRefinementStrategy]: Constructing automaton from 1 perfect and 1 imperfect interpolant sequences. [2018-11-18 15:44:51,318 INFO L327 seRefinementStrategy]: Number of different interpolants: perfect sequences [5] imperfect sequences [8] total 10 [2018-11-18 15:44:51,319 INFO L459 AbstractCegarLoop]: Interpolant automaton has 10 states [2018-11-18 15:44:51,319 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 10 interpolants. [2018-11-18 15:44:51,319 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=21, Invalid=69, Unknown=0, NotChecked=0, Total=90 [2018-11-18 15:44:51,319 INFO L87 Difference]: Start difference. First operand 48 states and 65 transitions. Second operand 10 states. [2018-11-18 15:44:51,467 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-11-18 15:44:51,467 INFO L93 Difference]: Finished difference Result 54 states and 70 transitions. [2018-11-18 15:44:51,468 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 8 states. [2018-11-18 15:44:51,468 INFO L78 Accepts]: Start accepts. Automaton has 10 states. Word has length 19 [2018-11-18 15:44:51,468 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-11-18 15:44:51,469 INFO L225 Difference]: With dead ends: 54 [2018-11-18 15:44:51,469 INFO L226 Difference]: Without dead ends: 42 [2018-11-18 15:44:51,469 INFO L604 BasicCegarLoop]: 0 DeclaredPredicates, 29 GetRequests, 19 SyntacticMatches, 0 SemanticMatches, 10 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 13 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=34, Invalid=98, Unknown=0, NotChecked=0, Total=132 [2018-11-18 15:44:51,469 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 42 states. [2018-11-18 15:44:51,472 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 42 to 42. [2018-11-18 15:44:51,473 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 42 states. [2018-11-18 15:44:51,473 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 42 states to 42 states and 53 transitions. [2018-11-18 15:44:51,474 INFO L78 Accepts]: Start accepts. Automaton has 42 states and 53 transitions. Word has length 19 [2018-11-18 15:44:51,474 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-11-18 15:44:51,474 INFO L480 AbstractCegarLoop]: Abstraction has 42 states and 53 transitions. [2018-11-18 15:44:51,474 INFO L481 AbstractCegarLoop]: Interpolant automaton has 10 states. [2018-11-18 15:44:51,474 INFO L276 IsEmpty]: Start isEmpty. Operand 42 states and 53 transitions. [2018-11-18 15:44:51,474 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 21 [2018-11-18 15:44:51,475 INFO L367 BasicCegarLoop]: Found error trace [2018-11-18 15:44:51,475 INFO L375 BasicCegarLoop]: trace histogram [2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-11-18 15:44:51,475 INFO L423 AbstractCegarLoop]: === Iteration 4 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2018-11-18 15:44:51,475 INFO L141 PredicateUnifier]: Initialized classic predicate unifier [2018-11-18 15:44:51,475 INFO L82 PathProgramCache]: Analyzing trace with hash 1546781750, now seen corresponding path program 1 times [2018-11-18 15:44:51,475 INFO L223 ckRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-11-18 15:44:51,475 INFO L69 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-11-18 15:44:51,476 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:51,476 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-11-18 15:44:51,477 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:51,482 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-11-18 15:44:51,543 INFO L134 CoverageAnalysis]: Checked inductivity of 2 backedges. 1 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-11-18 15:44:51,543 INFO L300 seRefinementStrategy]: The current sequences of interpolants are not accepted, trying to find more. [2018-11-18 15:44:51,543 INFO L223 ckRefinementStrategy]: Switched to mode Z3_FP No working directory specified, using /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/z3 Starting monitored process 3 with z3 -smt2 -in SMTLIB2_COMPLIANT=true -t:12000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 3 with z3 -smt2 -in SMTLIB2_COMPLIANT=true -t:12000 [2018-11-18 15:44:51,551 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-11-18 15:44:51,556 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-11-18 15:44:51,558 INFO L273 TraceCheckSpWp]: Computing forward predicates... [2018-11-18 15:44:51,599 INFO L134 CoverageAnalysis]: Checked inductivity of 2 backedges. 1 proven. 1 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-11-18 15:44:51,614 INFO L312 seRefinementStrategy]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences. [2018-11-18 15:44:51,614 INFO L327 seRefinementStrategy]: Number of different interpolants: perfect sequences [] imperfect sequences [8, 8] total 11 [2018-11-18 15:44:51,615 INFO L459 AbstractCegarLoop]: Interpolant automaton has 11 states [2018-11-18 15:44:51,615 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 11 interpolants. [2018-11-18 15:44:51,615 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=24, Invalid=86, Unknown=0, NotChecked=0, Total=110 [2018-11-18 15:44:51,615 INFO L87 Difference]: Start difference. First operand 42 states and 53 transitions. Second operand 11 states. [2018-11-18 15:44:51,880 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-11-18 15:44:51,880 INFO L93 Difference]: Finished difference Result 86 states and 113 transitions. [2018-11-18 15:44:51,880 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 11 states. [2018-11-18 15:44:51,881 INFO L78 Accepts]: Start accepts. Automaton has 11 states. Word has length 20 [2018-11-18 15:44:51,881 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-11-18 15:44:51,882 INFO L225 Difference]: With dead ends: 86 [2018-11-18 15:44:51,882 INFO L226 Difference]: Without dead ends: 82 [2018-11-18 15:44:51,883 INFO L604 BasicCegarLoop]: 0 DeclaredPredicates, 33 GetRequests, 17 SyntacticMatches, 2 SemanticMatches, 14 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 31 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=55, Invalid=185, Unknown=0, NotChecked=0, Total=240 [2018-11-18 15:44:51,883 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 82 states. [2018-11-18 15:44:51,893 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 82 to 78. [2018-11-18 15:44:51,893 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 78 states. [2018-11-18 15:44:51,894 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 78 states to 78 states and 103 transitions. [2018-11-18 15:44:51,895 INFO L78 Accepts]: Start accepts. Automaton has 78 states and 103 transitions. Word has length 20 [2018-11-18 15:44:51,895 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-11-18 15:44:51,895 INFO L480 AbstractCegarLoop]: Abstraction has 78 states and 103 transitions. [2018-11-18 15:44:51,895 INFO L481 AbstractCegarLoop]: Interpolant automaton has 11 states. [2018-11-18 15:44:51,895 INFO L276 IsEmpty]: Start isEmpty. Operand 78 states and 103 transitions. [2018-11-18 15:44:51,896 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 49 [2018-11-18 15:44:51,896 INFO L367 BasicCegarLoop]: Found error trace [2018-11-18 15:44:51,896 INFO L375 BasicCegarLoop]: trace histogram [6, 5, 5, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-11-18 15:44:51,897 INFO L423 AbstractCegarLoop]: === Iteration 5 === [__VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2018-11-18 15:44:51,897 INFO L141 PredicateUnifier]: Initialized classic predicate unifier [2018-11-18 15:44:51,897 INFO L82 PathProgramCache]: Analyzing trace with hash -1112674801, now seen corresponding path program 1 times [2018-11-18 15:44:51,897 INFO L223 ckRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-11-18 15:44:51,897 INFO L69 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-11-18 15:44:51,898 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:51,898 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-11-18 15:44:51,898 INFO L119 rtionOrderModulation]: Craig_TreeInterpolation forces the order to NOT_INCREMENTALLY [2018-11-18 15:44:51,907 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-11-18 15:44:51,971 INFO L134 CoverageAnalysis]: Checked inductivity of 50 backedges. 14 proven. 14 refuted. 0 times theorem prover too weak. 22 trivial. 0 not checked. [2018-11-18 15:44:51,972 INFO L300 seRefinementStrategy]: The current sequences of interpolants are not accepted, trying to find more. [2018-11-18 15:44:51,972 INFO L223 ckRefinementStrategy]: Switched to mode Z3_FP No working directory specified, using /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/z3 Starting monitored process 4 with z3 -smt2 -in SMTLIB2_COMPLIANT=true -t:12000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 4 with z3 -smt2 -in SMTLIB2_COMPLIANT=true -t:12000 [2018-11-18 15:44:51,985 INFO L103 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-11-18 15:44:51,994 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-11-18 15:44:51,996 INFO L273 TraceCheckSpWp]: Computing forward predicates... [2018-11-18 15:44:52,026 INFO L134 CoverageAnalysis]: Checked inductivity of 50 backedges. 14 proven. 14 refuted. 0 times theorem prover too weak. 22 trivial. 0 not checked. [2018-11-18 15:44:52,040 INFO L312 seRefinementStrategy]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences. [2018-11-18 15:44:52,041 INFO L327 seRefinementStrategy]: Number of different interpolants: perfect sequences [] imperfect sequences [9, 10] total 11 [2018-11-18 15:44:52,041 INFO L459 AbstractCegarLoop]: Interpolant automaton has 11 states [2018-11-18 15:44:52,041 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 11 interpolants. [2018-11-18 15:44:52,042 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=23, Invalid=87, Unknown=0, NotChecked=0, Total=110 [2018-11-18 15:44:52,042 INFO L87 Difference]: Start difference. First operand 78 states and 103 transitions. Second operand 11 states. [2018-11-18 15:44:52,171 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-11-18 15:44:52,171 INFO L93 Difference]: Finished difference Result 82 states and 106 transitions. [2018-11-18 15:44:52,171 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 10 states. [2018-11-18 15:44:52,172 INFO L78 Accepts]: Start accepts. Automaton has 11 states. Word has length 48 [2018-11-18 15:44:52,172 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-11-18 15:44:52,172 INFO L225 Difference]: With dead ends: 82 [2018-11-18 15:44:52,172 INFO L226 Difference]: Without dead ends: 0 [2018-11-18 15:44:52,173 INFO L604 BasicCegarLoop]: 0 DeclaredPredicates, 68 GetRequests, 51 SyntacticMatches, 3 SemanticMatches, 14 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 27 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=52, Invalid=188, Unknown=0, NotChecked=0, Total=240 [2018-11-18 15:44:52,173 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 0 states. [2018-11-18 15:44:52,173 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 0 to 0. [2018-11-18 15:44:52,173 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 0 states. [2018-11-18 15:44:52,173 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 0 states to 0 states and 0 transitions. [2018-11-18 15:44:52,173 INFO L78 Accepts]: Start accepts. Automaton has 0 states and 0 transitions. Word has length 48 [2018-11-18 15:44:52,173 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-11-18 15:44:52,173 INFO L480 AbstractCegarLoop]: Abstraction has 0 states and 0 transitions. [2018-11-18 15:44:52,173 INFO L481 AbstractCegarLoop]: Interpolant automaton has 11 states. [2018-11-18 15:44:52,173 INFO L276 IsEmpty]: Start isEmpty. Operand 0 states and 0 transitions. [2018-11-18 15:44:52,174 INFO L282 IsEmpty]: Finished isEmpty. No accepting run. [2018-11-18 15:44:52,176 INFO L343 DoubleDeckerVisitor]: Before removal of dead ends 0 states and 0 transitions. [2018-11-18 15:44:52,333 INFO L428 ceAbstractionStarter]: At program point ULTIMATE.initFINAL(line -1) the Hoare annotation is: true [2018-11-18 15:44:52,333 INFO L425 ceAbstractionStarter]: For program point ULTIMATE.initEXIT(line -1) no Hoare annotation was computed. [2018-11-18 15:44:52,333 INFO L425 ceAbstractionStarter]: For program point ULTIMATE.startEXIT(line -1) no Hoare annotation was computed. [2018-11-18 15:44:52,333 INFO L428 ceAbstractionStarter]: At program point L-1(line -1) the Hoare annotation is: true [2018-11-18 15:44:52,333 INFO L428 ceAbstractionStarter]: At program point ULTIMATE.startENTRY(line -1) the Hoare annotation is: true [2018-11-18 15:44:52,334 INFO L425 ceAbstractionStarter]: For program point ULTIMATE.startFINAL(line -1) no Hoare annotation was computed. [2018-11-18 15:44:52,334 INFO L421 ceAbstractionStarter]: At program point L31(line 31) the Hoare annotation is: (and (<= (+ main_~t~0 1) main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,334 INFO L428 ceAbstractionStarter]: At program point L60(lines 11 63) the Hoare annotation is: true [2018-11-18 15:44:52,334 INFO L421 ceAbstractionStarter]: At program point L27(line 27) the Hoare annotation is: (and (<= (+ main_~t~0 1) main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,334 INFO L421 ceAbstractionStarter]: At program point L27-1(line 27) the Hoare annotation is: (and (<= (+ main_~t~0 1) main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,334 INFO L425 ceAbstractionStarter]: For program point mainEXIT(lines 10 63) no Hoare annotation was computed. [2018-11-18 15:44:52,334 INFO L425 ceAbstractionStarter]: For program point L56(line 56) no Hoare annotation was computed. [2018-11-18 15:44:52,334 INFO L425 ceAbstractionStarter]: For program point L52(lines 52 54) no Hoare annotation was computed. [2018-11-18 15:44:52,334 INFO L425 ceAbstractionStarter]: For program point L19(lines 19 23) no Hoare annotation was computed. [2018-11-18 15:44:52,334 INFO L425 ceAbstractionStarter]: For program point L15(line 15) no Hoare annotation was computed. [2018-11-18 15:44:52,335 INFO L425 ceAbstractionStarter]: For program point L15-1(line 15) no Hoare annotation was computed. [2018-11-18 15:44:52,335 INFO L425 ceAbstractionStarter]: For program point L40(lines 40 54) no Hoare annotation was computed. [2018-11-18 15:44:52,335 INFO L421 ceAbstractionStarter]: At program point L40-1(lines 40 54) the Hoare annotation is: (and (<= (+ main_~t~0 1) main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,335 INFO L421 ceAbstractionStarter]: At program point L36(line 36) the Hoare annotation is: (and (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,335 INFO L421 ceAbstractionStarter]: At program point L36-1(line 36) the Hoare annotation is: (and (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,335 INFO L425 ceAbstractionStarter]: For program point L32(line 32) no Hoare annotation was computed. [2018-11-18 15:44:52,336 INFO L425 ceAbstractionStarter]: For program point L28(line 28) no Hoare annotation was computed. [2018-11-18 15:44:52,336 INFO L425 ceAbstractionStarter]: For program point L24(lines 24 26) no Hoare annotation was computed. [2018-11-18 15:44:52,336 INFO L421 ceAbstractionStarter]: At program point L20(line 20) the Hoare annotation is: (and (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,336 INFO L421 ceAbstractionStarter]: At program point L20-1(line 20) the Hoare annotation is: (and (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,336 INFO L425 ceAbstractionStarter]: For program point L45(lines 45 49) no Hoare annotation was computed. [2018-11-18 15:44:52,337 INFO L425 ceAbstractionStarter]: For program point L41(lines 41 50) no Hoare annotation was computed. [2018-11-18 15:44:52,337 INFO L421 ceAbstractionStarter]: At program point L46(line 46) the Hoare annotation is: (and (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,337 INFO L421 ceAbstractionStarter]: At program point L46-1(line 46) the Hoare annotation is: (and (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,337 INFO L425 ceAbstractionStarter]: For program point mainFINAL(lines 10 63) no Hoare annotation was computed. [2018-11-18 15:44:52,337 INFO L421 ceAbstractionStarter]: At program point L42(line 42) the Hoare annotation is: (and (<= (+ main_~t~0 1) main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,337 INFO L421 ceAbstractionStarter]: At program point L42-1(line 42) the Hoare annotation is: (and (<= (+ main_~t~0 1) main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,337 INFO L425 ceAbstractionStarter]: For program point L34-1(lines 34 58) no Hoare annotation was computed. [2018-11-18 15:44:52,337 INFO L421 ceAbstractionStarter]: At program point L34-3(lines 34 58) the Hoare annotation is: (and (<= 1 main_~tagbuf_len~0) (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,337 INFO L421 ceAbstractionStarter]: At program point L34-4(lines 34 58) the Hoare annotation is: (and (<= 1 main_~tagbuf_len~0) (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,337 INFO L428 ceAbstractionStarter]: At program point mainENTRY(lines 10 63) the Hoare annotation is: true [2018-11-18 15:44:52,338 INFO L421 ceAbstractionStarter]: At program point L59(line 59) the Hoare annotation is: (and (<= 1 main_~tagbuf_len~0) (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,338 INFO L421 ceAbstractionStarter]: At program point L55(line 55) the Hoare annotation is: (and (<= (+ main_~t~0 1) main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,338 INFO L425 ceAbstractionStarter]: For program point L18-1(lines 18 30) no Hoare annotation was computed. [2018-11-18 15:44:52,338 INFO L421 ceAbstractionStarter]: At program point L18-3(lines 18 30) the Hoare annotation is: (and (<= main_~t~0 main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,338 INFO L421 ceAbstractionStarter]: At program point L18-4(lines 18 30) the Hoare annotation is: (and (<= (+ main_~t~0 1) main_~tagbuf_len~0) (<= 0 main_~t~0)) [2018-11-18 15:44:52,338 INFO L425 ceAbstractionStarter]: For program point L43(line 43) no Hoare annotation was computed. [2018-11-18 15:44:52,338 INFO L425 ceAbstractionStarter]: For program point L35(lines 35 39) no Hoare annotation was computed. [2018-11-18 15:44:52,338 INFO L425 ceAbstractionStarter]: For program point __VERIFIER_assertErr0ASSERT_VIOLATIONERROR_FUNCTION(line 5) no Hoare annotation was computed. [2018-11-18 15:44:52,338 INFO L428 ceAbstractionStarter]: At program point __VERIFIER_assertENTRY(lines 3 8) the Hoare annotation is: true [2018-11-18 15:44:52,338 INFO L425 ceAbstractionStarter]: For program point __VERIFIER_assertEXIT(lines 3 8) no Hoare annotation was computed. [2018-11-18 15:44:52,339 INFO L425 ceAbstractionStarter]: For program point L5(line 5) no Hoare annotation was computed. [2018-11-18 15:44:52,339 INFO L425 ceAbstractionStarter]: For program point L4(lines 4 6) no Hoare annotation was computed. [2018-11-18 15:44:52,339 INFO L425 ceAbstractionStarter]: For program point L4-2(lines 3 8) no Hoare annotation was computed. [2018-11-18 15:44:52,347 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction CFG 18.11 03:44:52 BoogieIcfgContainer [2018-11-18 15:44:52,347 INFO L132 PluginConnector]: ------------------------ END TraceAbstraction---------------------------- [2018-11-18 15:44:52,347 INFO L113 PluginConnector]: ------------------------Witness Printer---------------------------- [2018-11-18 15:44:52,347 INFO L271 PluginConnector]: Initializing Witness Printer... [2018-11-18 15:44:52,348 INFO L276 PluginConnector]: Witness Printer initialized [2018-11-18 15:44:52,348 INFO L185 PluginConnector]: Executing the observer RCFGCatcher from plugin Witness Printer for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 18.11 03:44:50" (3/4) ... [2018-11-18 15:44:52,350 INFO L144 WitnessPrinter]: Generating witness for correct program [2018-11-18 15:44:52,354 INFO L333 RCFGBacktranslator]: Ignoring RootEdge to procedure ULTIMATE.init [2018-11-18 15:44:52,354 INFO L333 RCFGBacktranslator]: Ignoring RootEdge to procedure main [2018-11-18 15:44:52,355 INFO L333 RCFGBacktranslator]: Ignoring RootEdge to procedure __VERIFIER_assert [2018-11-18 15:44:52,357 INFO L846 BoogieBacktranslator]: Reduced CFG by removing 14 nodes and edges [2018-11-18 15:44:52,358 INFO L846 BoogieBacktranslator]: Reduced CFG by removing 7 nodes and edges [2018-11-18 15:44:52,358 INFO L846 BoogieBacktranslator]: Reduced CFG by removing 1 nodes and edges [2018-11-18 15:44:52,396 INFO L145 WitnessManager]: Wrote witness to /tmp/vcloud-vcloud-master/worker/working_dir_aa447f23-6270-48fc-94b7-4c342419b0ce/bin-2019/uautomizer/witness.graphml [2018-11-18 15:44:52,396 INFO L132 PluginConnector]: ------------------------ END Witness Printer---------------------------- [2018-11-18 15:44:52,397 INFO L168 Benchmark]: Toolchain (without parser) took 2054.07 ms. Allocated memory was 1.0 GB in the beginning and 1.1 GB in the end (delta: 117.4 MB). Free memory was 953.8 MB in the beginning and 831.4 MB in the end (delta: 122.4 MB). Peak memory consumption was 239.8 MB. Max. memory is 11.5 GB. [2018-11-18 15:44:52,398 INFO L168 Benchmark]: CDTParser took 0.15 ms. Allocated memory is still 1.0 GB. Free memory is still 985.4 MB. There was no memory consumed. Max. memory is 11.5 GB. [2018-11-18 15:44:52,399 INFO L168 Benchmark]: CACSL2BoogieTranslator took 164.59 ms. Allocated memory is still 1.0 GB. Free memory was 953.8 MB in the beginning and 943.0 MB in the end (delta: 10.7 MB). Peak memory consumption was 10.7 MB. Max. memory is 11.5 GB. [2018-11-18 15:44:52,399 INFO L168 Benchmark]: Boogie Preprocessor took 18.02 ms. Allocated memory is still 1.0 GB. Free memory was 943.0 MB in the beginning and 940.3 MB in the end (delta: 2.7 MB). Peak memory consumption was 2.7 MB. Max. memory is 11.5 GB. [2018-11-18 15:44:52,399 INFO L168 Benchmark]: RCFGBuilder took 205.65 ms. Allocated memory was 1.0 GB in the beginning and 1.1 GB in the end (delta: 117.4 MB). Free memory was 940.3 MB in the beginning and 1.1 GB in the end (delta: -156.8 MB). Peak memory consumption was 22.3 MB. Max. memory is 11.5 GB. [2018-11-18 15:44:52,399 INFO L168 Benchmark]: TraceAbstraction took 1613.85 ms. Allocated memory is still 1.1 GB. Free memory was 1.1 GB in the beginning and 834.7 MB in the end (delta: 262.4 MB). Peak memory consumption was 262.4 MB. Max. memory is 11.5 GB. [2018-11-18 15:44:52,399 INFO L168 Benchmark]: Witness Printer took 49.31 ms. Allocated memory is still 1.1 GB. Free memory was 834.7 MB in the beginning and 831.4 MB in the end (delta: 3.3 MB). Peak memory consumption was 3.3 MB. Max. memory is 11.5 GB. [2018-11-18 15:44:52,401 INFO L336 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * CDTParser took 0.15 ms. Allocated memory is still 1.0 GB. Free memory is still 985.4 MB. There was no memory consumed. Max. memory is 11.5 GB. * CACSL2BoogieTranslator took 164.59 ms. Allocated memory is still 1.0 GB. Free memory was 953.8 MB in the beginning and 943.0 MB in the end (delta: 10.7 MB). Peak memory consumption was 10.7 MB. Max. memory is 11.5 GB. * Boogie Preprocessor took 18.02 ms. Allocated memory is still 1.0 GB. Free memory was 943.0 MB in the beginning and 940.3 MB in the end (delta: 2.7 MB). Peak memory consumption was 2.7 MB. Max. memory is 11.5 GB. * RCFGBuilder took 205.65 ms. Allocated memory was 1.0 GB in the beginning and 1.1 GB in the end (delta: 117.4 MB). Free memory was 940.3 MB in the beginning and 1.1 GB in the end (delta: -156.8 MB). Peak memory consumption was 22.3 MB. Max. memory is 11.5 GB. * TraceAbstraction took 1613.85 ms. Allocated memory is still 1.1 GB. Free memory was 1.1 GB in the beginning and 834.7 MB in the end (delta: 262.4 MB). Peak memory consumption was 262.4 MB. Max. memory is 11.5 GB. * Witness Printer took 49.31 ms. Allocated memory is still 1.1 GB. Free memory was 834.7 MB in the beginning and 831.4 MB in the end (delta: 3.3 MB). Peak memory consumption was 3.3 MB. Max. memory is 11.5 GB. * Results from de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: - PositiveResult [Line: 5]: call of __VERIFIER_error() unreachable For all program executions holds that call of __VERIFIER_error() unreachable at this location - AllSpecificationsHoldResult: All specifications hold 1 specifications checked. All of them hold - InvariantResult [Line: 11]: Loop Invariant Derived loop invariant: 1 - InvariantResult [Line: 18]: Loop Invariant Derived loop invariant: t <= tagbuf_len && 0 <= t - InvariantResult [Line: 34]: Loop Invariant Derived loop invariant: (1 <= tagbuf_len && t <= tagbuf_len) && 0 <= t - StatisticsResult: Ultimate Automizer benchmark data CFG has 4 procedures, 49 locations, 1 error locations. SAFE Result, 1.5s OverallTime, 5 OverallIterations, 6 TraceHistogramMax, 0.7s AutomataDifference, 0.0s DeadEndRemovalTime, 0.1s HoareAnnotationTime, HoareTripleCheckerStatistics: 220 SDtfs, 151 SDslu, 701 SDs, 0 SdLazy, 730 SolverSat, 151 SolverUnsat, 0 SolverUnknown, 0 SolverNotchecked, 0.4s Time, PredicateUnifierStatistics: 0 DeclaredPredicates, 138 GetRequests, 91 SyntacticMatches, 5 SemanticMatches, 42 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 71 ImplicationChecksByTransitivity, 0.3s Time, 0.0s BasicInterpolantAutomatonTime, BiggestAbstraction: size=78occurred in iteration=4, traceCheckStatistics: No data available, InterpolantConsolidationStatistics: No data available, PathInvariantsStatistics: No data available, 0/0 InterpolantCoveringCapability, TotalInterpolationStatistics: No data available, 0.0s AbstIntTime, 0 AbstIntIterations, 0 AbstIntStrong, NaN AbsIntWeakeningRatio, NaN AbsIntAvgWeakeningVarsNumRemoved, NaN AbsIntAvgWeakenedConjuncts, 0.0s DumpTime, AutomataMinimizationStatistics: 0.0s AutomataMinimizationTime, 5 MinimizatonAttempts, 4 StatesRemovedByMinimization, 1 NontrivialMinimizations, HoareAnnotationStatistics: 0.0s HoareAnnotationTime, 24 LocationsWithAnnotation, 69 PreInvPairs, 103 NumberOfFragments, 157 HoareAnnotationTreeSize, 69 FomulaSimplifications, 124 FormulaSimplificationTreeSizeReduction, 0.0s HoareSimplificationTime, 24 FomulaSimplificationsInter, 124 FormulaSimplificationTreeSizeReductionInter, 0.1s HoareSimplificationTimeInter, RefinementEngineStatistics: TraceCheckStatistics: 0.0s SsaConstructionTime, 0.0s SatisfiabilityAnalysisTime, 0.3s InterpolantComputationTime, 200 NumberOfCodeBlocks, 200 NumberOfCodeBlocksAsserted, 8 NumberOfCheckSat, 192 ConstructedInterpolants, 0 QuantifiedInterpolants, 13726 SizeOfPredicates, 10 NumberOfNonLiveVariables, 178 ConjunctsInSsa, 41 ConjunctsInUnsatCore, 8 InterpolantComputations, 3 PerfectInterpolantSequences, 77/108 InterpolantCoveringCapability, InvariantSynthesisStatistics: No data available, InterpolantConsolidationStatistics: No data available, ReuseStatistics: No data available RESULT: Ultimate proved your program to be correct! Received shutdown request...