/usr/bin/java -Xmx8000000000 -Xss4m -jar ./plugins/org.eclipse.equinox.launcher_1.5.800.v20200727-1323.jar -data @noDefault -ultimatedata ./data -tc ../../../trunk/examples/toolchains/AutomizerC.xml -s ../../../trunk/examples/settings/automizer/acceleratedInterpolation/acceleratedInterpolationFastUPR_32.epf -i ../../../trunk/examples/svcomp/systemc/transmitter.01.cil.c -------------------------------------------------------------------------------- This is Ultimate 0.2.0-7d8eed3 [2020-11-07 02:19:54,683 INFO L177 SettingsManager]: Resetting all preferences to default values... [2020-11-07 02:19:54,686 INFO L181 SettingsManager]: Resetting UltimateCore preferences to default values [2020-11-07 02:19:54,726 INFO L184 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2020-11-07 02:19:54,727 INFO L181 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2020-11-07 02:19:54,729 INFO L181 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2020-11-07 02:19:54,731 INFO L181 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2020-11-07 02:19:54,733 INFO L181 SettingsManager]: Resetting LassoRanker preferences to default values [2020-11-07 02:19:54,735 INFO L181 SettingsManager]: Resetting Reaching Definitions preferences to default values [2020-11-07 02:19:54,737 INFO L181 SettingsManager]: Resetting SyntaxChecker preferences to default values [2020-11-07 02:19:54,748 INFO L181 SettingsManager]: Resetting Sifa preferences to default values [2020-11-07 02:19:54,750 INFO L184 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2020-11-07 02:19:54,751 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2020-11-07 02:19:54,752 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2020-11-07 02:19:54,753 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2020-11-07 02:19:54,755 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2020-11-07 02:19:54,756 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2020-11-07 02:19:54,757 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2020-11-07 02:19:54,759 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2020-11-07 02:19:54,761 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2020-11-07 02:19:54,763 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2020-11-07 02:19:54,765 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2020-11-07 02:19:54,766 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2020-11-07 02:19:54,767 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2020-11-07 02:19:54,770 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... [2020-11-07 02:19:54,771 INFO L184 SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring... [2020-11-07 02:19:54,771 INFO L181 SettingsManager]: Resetting TreeAutomizer preferences to default values [2020-11-07 02:19:54,772 INFO L181 SettingsManager]: Resetting IcfgToChc preferences to default values [2020-11-07 02:19:54,773 INFO L181 SettingsManager]: Resetting IcfgTransformer preferences to default values [2020-11-07 02:19:54,774 INFO L184 SettingsManager]: ReqToTest provides no preferences, ignoring... [2020-11-07 02:19:54,774 INFO L181 SettingsManager]: Resetting Boogie Printer preferences to default values [2020-11-07 02:19:54,775 INFO L181 SettingsManager]: Resetting ChcSmtPrinter preferences to default values [2020-11-07 02:19:54,777 INFO L181 SettingsManager]: Resetting ReqPrinter preferences to default values [2020-11-07 02:19:54,778 INFO L181 SettingsManager]: Resetting Witness Printer preferences to default values [2020-11-07 02:19:54,779 INFO L184 SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring... [2020-11-07 02:19:54,780 INFO L181 SettingsManager]: Resetting CDTParser preferences to default values [2020-11-07 02:19:54,781 INFO L184 SettingsManager]: AutomataScriptParser provides no preferences, ignoring... [2020-11-07 02:19:54,781 INFO L184 SettingsManager]: ReqParser provides no preferences, ignoring... [2020-11-07 02:19:54,781 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2020-11-07 02:19:54,783 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2020-11-07 02:19:54,784 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2020-11-07 02:19:54,785 INFO L101 SettingsManager]: Beginning loading settings from /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/settings/automizer/acceleratedInterpolation/acceleratedInterpolationFastUPR_32.epf [2020-11-07 02:19:54,799 INFO L113 SettingsManager]: Loading preferences was successful [2020-11-07 02:19:54,800 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2020-11-07 02:19:54,802 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2020-11-07 02:19:54,803 INFO L138 SettingsManager]: * sizeof long=4 [2020-11-07 02:19:54,803 INFO L138 SettingsManager]: * Overapproximate operations on floating types=true [2020-11-07 02:19:54,803 INFO L138 SettingsManager]: * sizeof POINTER=4 [2020-11-07 02:19:54,803 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2020-11-07 02:19:54,804 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2020-11-07 02:19:54,804 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2020-11-07 02:19:54,804 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2020-11-07 02:19:54,804 INFO L138 SettingsManager]: * sizeof long double=12 [2020-11-07 02:19:54,805 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2020-11-07 02:19:54,805 INFO L138 SettingsManager]: * Use constant arrays=true [2020-11-07 02:19:54,805 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2020-11-07 02:19:54,806 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2020-11-07 02:19:54,806 INFO L138 SettingsManager]: * Size of a code block=SingleStatement [2020-11-07 02:19:54,806 INFO L138 SettingsManager]: * To the following directory=./dump/ [2020-11-07 02:19:54,806 INFO L138 SettingsManager]: * SMT solver=External_DefaultMode [2020-11-07 02:19:54,807 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-11-07 02:19:54,807 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2020-11-07 02:19:54,807 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=AcceleratedInterpolation [2020-11-07 02:19:54,808 INFO L138 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2020-11-07 02:19:54,808 INFO L138 SettingsManager]: * Use separate solver for trace checks=false WARNING: An illegal reflective access operation has occurred WARNING: Illegal reflective access by com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 (file:/storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/plugins/com.sun.xml.bind_2.2.0.v201505121915.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int) WARNING: Please consider reporting this to the maintainers of com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations WARNING: All illegal access operations will be denied in a future release [2020-11-07 02:19:55,208 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2020-11-07 02:19:55,244 INFO L261 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2020-11-07 02:19:55,248 INFO L217 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2020-11-07 02:19:55,249 INFO L271 PluginConnector]: Initializing CDTParser... [2020-11-07 02:19:55,250 INFO L275 PluginConnector]: CDTParser initialized [2020-11-07 02:19:55,251 INFO L432 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/systemc/transmitter.01.cil.c [2020-11-07 02:19:55,344 INFO L220 CDTParser]: Created temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/eb0c1e7b2/2f8023bc6ad74f2190fb696d08fa00a2/FLAG961fbff66 [2020-11-07 02:19:56,150 INFO L306 CDTParser]: Found 1 translation units. [2020-11-07 02:19:56,151 INFO L160 CDTParser]: Scanning /storage/repos/ultimate/trunk/examples/svcomp/systemc/transmitter.01.cil.c [2020-11-07 02:19:56,170 INFO L349 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/eb0c1e7b2/2f8023bc6ad74f2190fb696d08fa00a2/FLAG961fbff66 [2020-11-07 02:19:56,448 INFO L357 CDTParser]: Successfully deleted /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/eb0c1e7b2/2f8023bc6ad74f2190fb696d08fa00a2 [2020-11-07 02:19:56,451 INFO L299 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2020-11-07 02:19:56,458 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2020-11-07 02:19:56,460 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2020-11-07 02:19:56,460 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2020-11-07 02:19:56,465 INFO L275 PluginConnector]: CACSL2BoogieTranslator initialized [2020-11-07 02:19:56,466 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,469 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@847d14f and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56, skipping insertion in model container [2020-11-07 02:19:56,470 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,479 INFO L145 MainTranslator]: Starting translation in SV-COMP mode [2020-11-07 02:19:56,507 INFO L178 MainTranslator]: Built tables and reachable declarations [2020-11-07 02:19:56,718 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-11-07 02:19:56,730 INFO L203 MainTranslator]: Completed pre-run [2020-11-07 02:19:56,768 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-11-07 02:19:56,793 INFO L208 MainTranslator]: Completed translation [2020-11-07 02:19:56,794 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56 WrapperNode [2020-11-07 02:19:56,794 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2020-11-07 02:19:56,796 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2020-11-07 02:19:56,796 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2020-11-07 02:19:56,796 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2020-11-07 02:19:56,809 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,810 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,820 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,820 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,831 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,841 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,844 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (1/1) ... [2020-11-07 02:19:56,848 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2020-11-07 02:19:56,849 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2020-11-07 02:19:56,850 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2020-11-07 02:19:56,850 INFO L275 PluginConnector]: RCFGBuilder initialized [2020-11-07 02:19:56,851 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (1/1) ... No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-11-07 02:19:56,939 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2020-11-07 02:19:56,940 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2020-11-07 02:19:56,940 INFO L138 BoogieDeclarations]: Found implementation of procedure reach_error [2020-11-07 02:19:56,940 INFO L138 BoogieDeclarations]: Found implementation of procedure error [2020-11-07 02:19:56,940 INFO L138 BoogieDeclarations]: Found implementation of procedure master [2020-11-07 02:19:56,940 INFO L138 BoogieDeclarations]: Found implementation of procedure transmit1 [2020-11-07 02:19:56,941 INFO L138 BoogieDeclarations]: Found implementation of procedure is_master_triggered [2020-11-07 02:19:56,941 INFO L138 BoogieDeclarations]: Found implementation of procedure is_transmit1_triggered [2020-11-07 02:19:56,941 INFO L138 BoogieDeclarations]: Found implementation of procedure update_channels [2020-11-07 02:19:56,941 INFO L138 BoogieDeclarations]: Found implementation of procedure init_threads [2020-11-07 02:19:56,941 INFO L138 BoogieDeclarations]: Found implementation of procedure exists_runnable_thread [2020-11-07 02:19:56,941 INFO L138 BoogieDeclarations]: Found implementation of procedure eval [2020-11-07 02:19:56,942 INFO L138 BoogieDeclarations]: Found implementation of procedure fire_delta_events [2020-11-07 02:19:56,942 INFO L138 BoogieDeclarations]: Found implementation of procedure reset_delta_events [2020-11-07 02:19:56,942 INFO L138 BoogieDeclarations]: Found implementation of procedure activate_threads [2020-11-07 02:19:56,942 INFO L138 BoogieDeclarations]: Found implementation of procedure immediate_notify [2020-11-07 02:19:56,942 INFO L138 BoogieDeclarations]: Found implementation of procedure fire_time_events [2020-11-07 02:19:56,943 INFO L138 BoogieDeclarations]: Found implementation of procedure reset_time_events [2020-11-07 02:19:56,943 INFO L138 BoogieDeclarations]: Found implementation of procedure init_model [2020-11-07 02:19:56,943 INFO L138 BoogieDeclarations]: Found implementation of procedure stop_simulation [2020-11-07 02:19:56,943 INFO L138 BoogieDeclarations]: Found implementation of procedure start_simulation [2020-11-07 02:19:56,943 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2020-11-07 02:19:56,944 INFO L130 BoogieDeclarations]: Found specification of procedure abort [2020-11-07 02:19:56,944 INFO L130 BoogieDeclarations]: Found specification of procedure __assert_fail [2020-11-07 02:19:56,944 INFO L130 BoogieDeclarations]: Found specification of procedure reach_error [2020-11-07 02:19:56,944 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocOnStack [2020-11-07 02:19:56,944 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_int [2020-11-07 02:19:56,945 INFO L130 BoogieDeclarations]: Found specification of procedure error [2020-11-07 02:19:56,945 INFO L130 BoogieDeclarations]: Found specification of procedure is_master_triggered [2020-11-07 02:19:56,945 INFO L130 BoogieDeclarations]: Found specification of procedure is_transmit1_triggered [2020-11-07 02:19:56,945 INFO L130 BoogieDeclarations]: Found specification of procedure immediate_notify [2020-11-07 02:19:56,945 INFO L130 BoogieDeclarations]: Found specification of procedure master [2020-11-07 02:19:56,945 INFO L130 BoogieDeclarations]: Found specification of procedure transmit1 [2020-11-07 02:19:56,946 INFO L130 BoogieDeclarations]: Found specification of procedure update_channels [2020-11-07 02:19:56,946 INFO L130 BoogieDeclarations]: Found specification of procedure init_threads [2020-11-07 02:19:56,946 INFO L130 BoogieDeclarations]: Found specification of procedure exists_runnable_thread [2020-11-07 02:19:56,946 INFO L130 BoogieDeclarations]: Found specification of procedure eval [2020-11-07 02:19:56,946 INFO L130 BoogieDeclarations]: Found specification of procedure fire_delta_events [2020-11-07 02:19:56,947 INFO L130 BoogieDeclarations]: Found specification of procedure reset_delta_events [2020-11-07 02:19:56,947 INFO L130 BoogieDeclarations]: Found specification of procedure activate_threads [2020-11-07 02:19:56,947 INFO L130 BoogieDeclarations]: Found specification of procedure fire_time_events [2020-11-07 02:19:56,947 INFO L130 BoogieDeclarations]: Found specification of procedure reset_time_events [2020-11-07 02:19:56,947 INFO L130 BoogieDeclarations]: Found specification of procedure init_model [2020-11-07 02:19:56,947 INFO L130 BoogieDeclarations]: Found specification of procedure stop_simulation [2020-11-07 02:19:56,948 INFO L130 BoogieDeclarations]: Found specification of procedure start_simulation [2020-11-07 02:19:56,948 INFO L130 BoogieDeclarations]: Found specification of procedure main [2020-11-07 02:19:56,948 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2020-11-07 02:19:56,948 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int [2020-11-07 02:19:56,948 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2020-11-07 02:19:56,948 INFO L130 BoogieDeclarations]: Found specification of procedure write~int [2020-11-07 02:19:56,949 INFO L130 BoogieDeclarations]: Found specification of procedure read~int [2020-11-07 02:19:56,949 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.dealloc [2020-11-07 02:19:57,660 INFO L293 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2020-11-07 02:19:57,661 INFO L298 CfgBuilder]: Removed 5 assume(true) statements. [2020-11-07 02:19:57,663 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 07.11 02:19:57 BoogieIcfgContainer [2020-11-07 02:19:57,663 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2020-11-07 02:19:57,665 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2020-11-07 02:19:57,666 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2020-11-07 02:19:57,669 INFO L275 PluginConnector]: TraceAbstraction initialized [2020-11-07 02:19:57,670 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 07.11 02:19:56" (1/3) ... [2020-11-07 02:19:57,671 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@13f243f1 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 07.11 02:19:57, skipping insertion in model container [2020-11-07 02:19:57,671 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 07.11 02:19:56" (2/3) ... [2020-11-07 02:19:57,671 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@13f243f1 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 07.11 02:19:57, skipping insertion in model container [2020-11-07 02:19:57,671 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 07.11 02:19:57" (3/3) ... [2020-11-07 02:19:57,673 INFO L111 eAbstractionObserver]: Analyzing ICFG transmitter.01.cil.c [2020-11-07 02:19:57,692 INFO L179 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:AcceleratedInterpolation Determinization: PREDICATE_ABSTRACTION [2020-11-07 02:19:57,698 INFO L191 ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations. [2020-11-07 02:19:57,712 INFO L253 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2020-11-07 02:19:57,741 INFO L377 AbstractCegarLoop]: Interprodecural is true [2020-11-07 02:19:57,741 INFO L378 AbstractCegarLoop]: Hoare is true [2020-11-07 02:19:57,741 INFO L379 AbstractCegarLoop]: Compute interpolants for AcceleratedInterpolation [2020-11-07 02:19:57,741 INFO L380 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2020-11-07 02:19:57,742 INFO L381 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2020-11-07 02:19:57,742 INFO L382 AbstractCegarLoop]: Difference is false [2020-11-07 02:19:57,742 INFO L383 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2020-11-07 02:19:57,742 INFO L387 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2020-11-07 02:19:57,766 INFO L276 IsEmpty]: Start isEmpty. Operand 213 states. [2020-11-07 02:19:57,784 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 112 [2020-11-07 02:19:57,784 INFO L414 BasicCegarLoop]: Found error trace [2020-11-07 02:19:57,785 INFO L422 BasicCegarLoop]: trace histogram [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, 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, 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, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-11-07 02:19:57,786 INFO L429 AbstractCegarLoop]: === Iteration 1 === [reach_errorErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-07 02:19:57,793 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-07 02:19:57,794 INFO L82 PathProgramCache]: Analyzing trace with hash -1428806006, now seen corresponding path program 1 times [2020-11-07 02:19:57,805 INFO L162 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-11-07 02:19:57,806 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1419826580] [2020-11-07 02:19:57,806 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-07 02:19:57,903 INFO L328 leratedInterpolation]: No loops in this trace, falling back to nested interpolation [2020-11-07 02:19:58,038 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,295 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-11-07 02:19:58,303 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,331 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 22 [2020-11-07 02:19:58,334 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,337 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 32 [2020-11-07 02:19:58,339 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,353 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 35 [2020-11-07 02:19:58,358 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,381 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 42 [2020-11-07 02:19:58,385 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,390 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 48 [2020-11-07 02:19:58,416 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,460 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 2 [2020-11-07 02:19:58,464 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,472 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 13 [2020-11-07 02:19:58,476 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,488 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 75 [2020-11-07 02:19:58,496 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,504 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 86 [2020-11-07 02:19:58,510 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:19:58,556 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-11-07 02:19:58,559 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [1419826580] [2020-11-07 02:19:58,562 INFO L219 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-11-07 02:19:58,563 INFO L232 FreeRefinementEngine]: Number of different interpolants: perfect sequences [8] imperfect sequences [] total 8 [2020-11-07 02:19:58,563 INFO L155 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1502234938] [2020-11-07 02:19:58,571 INFO L461 AbstractCegarLoop]: Interpolant automaton has 8 states [2020-11-07 02:19:58,572 INFO L142 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-11-07 02:19:58,586 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 8 interpolants. [2020-11-07 02:19:58,589 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=18, Invalid=38, Unknown=0, NotChecked=0, Total=56 [2020-11-07 02:19:58,592 INFO L87 Difference]: Start difference. First operand 213 states. Second operand 8 states. [2020-11-07 02:20:01,988 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-11-07 02:20:01,989 INFO L93 Difference]: Finished difference Result 814 states and 1170 transitions. [2020-11-07 02:20:01,991 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 22 states. [2020-11-07 02:20:01,992 INFO L78 Accepts]: Start accepts. Automaton has 8 states. Word has length 111 [2020-11-07 02:20:01,993 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-11-07 02:20:02,020 INFO L225 Difference]: With dead ends: 814 [2020-11-07 02:20:02,020 INFO L226 Difference]: Without dead ends: 614 [2020-11-07 02:20:02,030 INFO L677 BasicCegarLoop]: 0 DeclaredPredicates, 48 GetRequests, 26 SyntacticMatches, 0 SemanticMatches, 22 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 117 ImplicationChecksByTransitivity, 0.4s TimeCoverageRelationStatistics Valid=168, Invalid=384, Unknown=0, NotChecked=0, Total=552 [2020-11-07 02:20:02,051 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 614 states. [2020-11-07 02:20:02,258 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 614 to 359. [2020-11-07 02:20:02,260 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 359 states. [2020-11-07 02:20:02,264 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 359 states to 359 states and 443 transitions. [2020-11-07 02:20:02,267 INFO L78 Accepts]: Start accepts. Automaton has 359 states and 443 transitions. Word has length 111 [2020-11-07 02:20:02,268 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-11-07 02:20:02,268 INFO L481 AbstractCegarLoop]: Abstraction has 359 states and 443 transitions. [2020-11-07 02:20:02,268 INFO L482 AbstractCegarLoop]: Interpolant automaton has 8 states. [2020-11-07 02:20:02,269 INFO L276 IsEmpty]: Start isEmpty. Operand 359 states and 443 transitions. [2020-11-07 02:20:02,274 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 113 [2020-11-07 02:20:02,274 INFO L414 BasicCegarLoop]: Found error trace [2020-11-07 02:20:02,274 INFO L422 BasicCegarLoop]: trace histogram [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, 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, 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, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-11-07 02:20:02,275 WARN L518 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2020-11-07 02:20:02,275 INFO L429 AbstractCegarLoop]: === Iteration 2 === [reach_errorErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-07 02:20:02,276 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-07 02:20:02,276 INFO L82 PathProgramCache]: Analyzing trace with hash -2138316646, now seen corresponding path program 1 times [2020-11-07 02:20:02,277 INFO L162 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-11-07 02:20:02,277 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [739398390] [2020-11-07 02:20:02,277 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-07 02:20:02,292 INFO L328 leratedInterpolation]: No loops in this trace, falling back to nested interpolation [2020-11-07 02:20:02,328 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,421 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-11-07 02:20:02,430 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,461 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 22 [2020-11-07 02:20:02,465 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,469 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 32 [2020-11-07 02:20:02,472 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,484 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 35 [2020-11-07 02:20:02,487 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,515 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 42 [2020-11-07 02:20:02,517 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,519 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 48 [2020-11-07 02:20:02,525 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,530 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 2 [2020-11-07 02:20:02,531 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,533 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 13 [2020-11-07 02:20:02,534 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,537 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 75 [2020-11-07 02:20:02,538 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,540 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 86 [2020-11-07 02:20:02,542 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:02,559 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-11-07 02:20:02,560 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [739398390] [2020-11-07 02:20:02,560 INFO L219 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-11-07 02:20:02,561 INFO L232 FreeRefinementEngine]: Number of different interpolants: perfect sequences [8] imperfect sequences [] total 8 [2020-11-07 02:20:02,561 INFO L155 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [752081775] [2020-11-07 02:20:02,562 INFO L461 AbstractCegarLoop]: Interpolant automaton has 8 states [2020-11-07 02:20:02,562 INFO L142 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-11-07 02:20:02,563 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 8 interpolants. [2020-11-07 02:20:02,563 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=16, Invalid=40, Unknown=0, NotChecked=0, Total=56 [2020-11-07 02:20:02,564 INFO L87 Difference]: Start difference. First operand 359 states and 443 transitions. Second operand 8 states. [2020-11-07 02:20:04,318 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-11-07 02:20:04,319 INFO L93 Difference]: Finished difference Result 846 states and 1094 transitions. [2020-11-07 02:20:04,319 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 14 states. [2020-11-07 02:20:04,320 INFO L78 Accepts]: Start accepts. Automaton has 8 states. Word has length 112 [2020-11-07 02:20:04,320 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-11-07 02:20:04,336 INFO L225 Difference]: With dead ends: 846 [2020-11-07 02:20:04,336 INFO L226 Difference]: Without dead ends: 530 [2020-11-07 02:20:04,344 INFO L677 BasicCegarLoop]: 0 DeclaredPredicates, 37 GetRequests, 21 SyntacticMatches, 0 SemanticMatches, 16 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 36 ImplicationChecksByTransitivity, 0.3s TimeCoverageRelationStatistics Valid=90, Invalid=216, Unknown=0, NotChecked=0, Total=306 [2020-11-07 02:20:04,345 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 530 states. [2020-11-07 02:20:04,432 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 530 to 350. [2020-11-07 02:20:04,432 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 350 states. [2020-11-07 02:20:04,436 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 350 states to 350 states and 428 transitions. [2020-11-07 02:20:04,437 INFO L78 Accepts]: Start accepts. Automaton has 350 states and 428 transitions. Word has length 112 [2020-11-07 02:20:04,437 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-11-07 02:20:04,437 INFO L481 AbstractCegarLoop]: Abstraction has 350 states and 428 transitions. [2020-11-07 02:20:04,437 INFO L482 AbstractCegarLoop]: Interpolant automaton has 8 states. [2020-11-07 02:20:04,438 INFO L276 IsEmpty]: Start isEmpty. Operand 350 states and 428 transitions. [2020-11-07 02:20:04,440 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 117 [2020-11-07 02:20:04,440 INFO L414 BasicCegarLoop]: Found error trace [2020-11-07 02:20:04,440 INFO L422 BasicCegarLoop]: trace histogram [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, 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, 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, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-11-07 02:20:04,440 WARN L518 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2020-11-07 02:20:04,441 INFO L429 AbstractCegarLoop]: === Iteration 3 === [reach_errorErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-07 02:20:04,441 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-07 02:20:04,442 INFO L82 PathProgramCache]: Analyzing trace with hash 247926262, now seen corresponding path program 1 times [2020-11-07 02:20:04,442 INFO L162 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-11-07 02:20:04,442 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1164308306] [2020-11-07 02:20:04,442 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-07 02:20:04,445 INFO L328 leratedInterpolation]: No loops in this trace, falling back to nested interpolation [2020-11-07 02:20:04,464 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,573 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-11-07 02:20:04,582 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,608 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 22 [2020-11-07 02:20:04,610 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,613 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 32 [2020-11-07 02:20:04,614 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,627 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 35 [2020-11-07 02:20:04,634 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,650 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 42 [2020-11-07 02:20:04,653 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,656 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 48 [2020-11-07 02:20:04,661 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,668 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 2 [2020-11-07 02:20:04,670 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,676 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 13 [2020-11-07 02:20:04,677 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,682 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 75 [2020-11-07 02:20:04,685 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,694 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 86 [2020-11-07 02:20:04,701 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:04,730 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-11-07 02:20:04,750 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [1164308306] [2020-11-07 02:20:04,750 INFO L219 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-11-07 02:20:04,750 INFO L232 FreeRefinementEngine]: Number of different interpolants: perfect sequences [7] imperfect sequences [] total 7 [2020-11-07 02:20:04,751 INFO L155 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1708190249] [2020-11-07 02:20:04,751 INFO L461 AbstractCegarLoop]: Interpolant automaton has 7 states [2020-11-07 02:20:04,752 INFO L142 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-11-07 02:20:04,752 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 7 interpolants. [2020-11-07 02:20:04,753 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=14, Invalid=28, Unknown=0, NotChecked=0, Total=42 [2020-11-07 02:20:04,753 INFO L87 Difference]: Start difference. First operand 350 states and 428 transitions. Second operand 7 states. [2020-11-07 02:20:06,825 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-11-07 02:20:06,825 INFO L93 Difference]: Finished difference Result 1289 states and 1732 transitions. [2020-11-07 02:20:06,826 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 15 states. [2020-11-07 02:20:06,826 INFO L78 Accepts]: Start accepts. Automaton has 7 states. Word has length 116 [2020-11-07 02:20:06,827 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-11-07 02:20:06,836 INFO L225 Difference]: With dead ends: 1289 [2020-11-07 02:20:06,836 INFO L226 Difference]: Without dead ends: 982 [2020-11-07 02:20:06,840 INFO L677 BasicCegarLoop]: 0 DeclaredPredicates, 44 GetRequests, 29 SyntacticMatches, 0 SemanticMatches, 15 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 48 ImplicationChecksByTransitivity, 0.3s TimeCoverageRelationStatistics Valid=91, Invalid=181, Unknown=0, NotChecked=0, Total=272 [2020-11-07 02:20:06,842 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 982 states. [2020-11-07 02:20:06,999 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 982 to 671. [2020-11-07 02:20:07,000 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 671 states. [2020-11-07 02:20:07,006 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 671 states to 671 states and 834 transitions. [2020-11-07 02:20:07,007 INFO L78 Accepts]: Start accepts. Automaton has 671 states and 834 transitions. Word has length 116 [2020-11-07 02:20:07,008 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-11-07 02:20:07,008 INFO L481 AbstractCegarLoop]: Abstraction has 671 states and 834 transitions. [2020-11-07 02:20:07,008 INFO L482 AbstractCegarLoop]: Interpolant automaton has 7 states. [2020-11-07 02:20:07,009 INFO L276 IsEmpty]: Start isEmpty. Operand 671 states and 834 transitions. [2020-11-07 02:20:07,012 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 149 [2020-11-07 02:20:07,012 INFO L414 BasicCegarLoop]: Found error trace [2020-11-07 02:20:07,013 INFO L422 BasicCegarLoop]: trace histogram [2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 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, 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, 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] [2020-11-07 02:20:07,013 WARN L518 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable2 [2020-11-07 02:20:07,014 INFO L429 AbstractCegarLoop]: === Iteration 4 === [reach_errorErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-07 02:20:07,014 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-07 02:20:07,014 INFO L82 PathProgramCache]: Analyzing trace with hash 2027254963, now seen corresponding path program 1 times [2020-11-07 02:20:07,015 INFO L162 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-11-07 02:20:07,015 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [614419470] [2020-11-07 02:20:07,015 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-07 02:20:07,123 WARN L194 SmtUtils]: Spent 100.00 ms on a formula simplification. DAG size of input: 46 DAG size of output: 38 [2020-11-07 02:20:07,486 INFO L316 leratedInterpolation]: Starting analysis with loop acceleration approximation UNDERAPPROXIMATION [2020-11-07 02:20:07,522 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,698 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 0 [2020-11-07 02:20:07,707 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,767 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 22 [2020-11-07 02:20:07,772 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,776 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 32 [2020-11-07 02:20:07,777 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,792 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 35 [2020-11-07 02:20:07,794 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,815 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 42 [2020-11-07 02:20:07,819 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,821 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 48 [2020-11-07 02:20:07,826 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,836 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 2 [2020-11-07 02:20:07,839 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,841 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 13 [2020-11-07 02:20:07,842 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,844 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 75 [2020-11-07 02:20:07,846 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,848 INFO L375 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 90 [2020-11-07 02:20:07,850 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-07 02:20:07,877 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-11-07 02:20:08,598 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [614419470] [2020-11-07 02:20:08,599 INFO L219 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-11-07 02:20:08,599 INFO L232 FreeRefinementEngine]: Number of different interpolants: perfect sequences [27] imperfect sequences [] total 27 [2020-11-07 02:20:08,599 INFO L155 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1412525568] [2020-11-07 02:20:08,600 INFO L461 AbstractCegarLoop]: Interpolant automaton has 28 states [2020-11-07 02:20:08,600 INFO L142 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES [2020-11-07 02:20:08,601 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 28 interpolants. [2020-11-07 02:20:08,602 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=149, Invalid=663, Unknown=0, NotChecked=0, Total=812 [2020-11-07 02:20:08,602 INFO L87 Difference]: Start difference. First operand 671 states and 834 transitions. Second operand 28 states. [2020-11-07 02:20:17,654 WARN L194 SmtUtils]: Spent 186.00 ms on a formula simplification. DAG size of input: 78 DAG size of output: 77 [2020-11-07 02:20:17,832 WARN L194 SmtUtils]: Spent 141.00 ms on a formula simplification. DAG size of input: 71 DAG size of output: 70 [2020-11-07 02:20:24,627 WARN L194 SmtUtils]: Spent 110.00 ms on a formula simplification that was a NOOP. DAG size: 78 [2020-11-07 02:20:26,411 WARN L194 SmtUtils]: Spent 140.00 ms on a formula simplification. DAG size of input: 72 DAG size of output: 71 [2020-11-07 02:20:26,663 WARN L194 SmtUtils]: Spent 194.00 ms on a formula simplification. DAG size of input: 79 DAG size of output: 78 [2020-11-07 02:20:26,891 WARN L194 SmtUtils]: Spent 150.00 ms on a formula simplification. DAG size of input: 75 DAG size of output: 74 [2020-11-07 02:20:27,199 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-11-07 02:20:27,199 INFO L93 Difference]: Finished difference Result 2466 states and 3317 transitions. [2020-11-07 02:20:27,200 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 171 states. [2020-11-07 02:20:27,201 INFO L78 Accepts]: Start accepts. Automaton has 28 states. Word has length 148 [2020-11-07 02:20:27,203 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-11-07 02:20:27,222 INFO L225 Difference]: With dead ends: 2466 [2020-11-07 02:20:27,222 INFO L226 Difference]: Without dead ends: 1839 [2020-11-07 02:20:27,241 INFO L677 BasicCegarLoop]: 0 DeclaredPredicates, 310 GetRequests, 114 SyntacticMatches, 2 SemanticMatches, 194 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 16193 ImplicationChecksByTransitivity, 10.9s TimeCoverageRelationStatistics Valid=6187, Invalid=32033, Unknown=0, NotChecked=0, Total=38220 [2020-11-07 02:20:27,244 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 1839 states. [2020-11-07 02:20:27,500 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 1839 to 1098. [2020-11-07 02:20:27,500 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 1098 states. [2020-11-07 02:20:27,508 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 1098 states to 1098 states and 1397 transitions. [2020-11-07 02:20:27,511 INFO L78 Accepts]: Start accepts. Automaton has 1098 states and 1397 transitions. Word has length 148 [2020-11-07 02:20:27,513 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-11-07 02:20:27,513 INFO L481 AbstractCegarLoop]: Abstraction has 1098 states and 1397 transitions. [2020-11-07 02:20:27,513 INFO L482 AbstractCegarLoop]: Interpolant automaton has 28 states. [2020-11-07 02:20:27,513 INFO L276 IsEmpty]: Start isEmpty. Operand 1098 states and 1397 transitions. [2020-11-07 02:20:27,518 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 192 [2020-11-07 02:20:27,518 INFO L414 BasicCegarLoop]: Found error trace [2020-11-07 02:20:27,519 INFO L422 BasicCegarLoop]: trace histogram [2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 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, 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, 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, 1] [2020-11-07 02:20:27,519 WARN L518 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3 [2020-11-07 02:20:27,520 INFO L429 AbstractCegarLoop]: === Iteration 5 === [reach_errorErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-07 02:20:27,520 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-07 02:20:27,520 INFO L82 PathProgramCache]: Analyzing trace with hash -1717488635, now seen corresponding path program 1 times [2020-11-07 02:20:27,521 INFO L162 FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES [2020-11-07 02:20:27,521 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [474655637] [2020-11-07 02:20:27,521 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-07 02:20:27,877 FATAL L? ?]: The Plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction has thrown an exception: java.lang.NullPointerException at de.uni_freiburg.informatik.ultimate.lib.acceleratedinterpolation.AcceleratedInterpolation.accelerateNestedLoops(AcceleratedInterpolation.java:569) at de.uni_freiburg.informatik.ultimate.lib.acceleratedinterpolation.AcceleratedInterpolation.acceleratedInterpolationCore(AcceleratedInterpolation.java:275) at de.uni_freiburg.informatik.ultimate.lib.acceleratedinterpolation.AcceleratedInterpolation.(AcceleratedInterpolation.java:227) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.IpTcStrategyModulePreferences.construct(IpTcStrategyModulePreferences.java:147) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.IpTcStrategyModuleBase.getOrConstruct(IpTcStrategyModuleBase.java:100) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.IpTcStrategyModuleBase.isCorrect(IpTcStrategyModuleBase.java:56) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.checkFeasibility(AutomatonFreeRefinementEngine.java:241) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.executeStrategy(AutomatonFreeRefinementEngine.java:165) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.(AutomatonFreeRefinementEngine.java:84) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.TraceAbstractionRefinementEngine.(TraceAbstractionRefinementEngine.java:74) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.BasicCegarLoop.isCounterexampleFeasible(BasicCegarLoop.java:511) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.AbstractCegarLoop.iterateInternal(AbstractCegarLoop.java:438) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.AbstractCegarLoop.iterate(AbstractCegarLoop.java:372) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.CegarLoopResult.iterate(CegarLoopResult.java:142) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionStarter.iterateNew(TraceAbstractionStarter.java:343) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionStarter.runCegarLoops(TraceAbstractionStarter.java:197) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionStarter.(TraceAbstractionStarter.java:149) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver.finish(TraceAbstractionObserver.java:124) at de.uni_freiburg.informatik.ultimate.core.coreplugin.PluginConnector.runObserver(PluginConnector.java:168) at de.uni_freiburg.informatik.ultimate.core.coreplugin.PluginConnector.runTool(PluginConnector.java:151) at de.uni_freiburg.informatik.ultimate.core.coreplugin.PluginConnector.run(PluginConnector.java:128) at de.uni_freiburg.informatik.ultimate.core.coreplugin.ToolchainWalker.executePluginConnector(ToolchainWalker.java:232) at de.uni_freiburg.informatik.ultimate.core.coreplugin.ToolchainWalker.processPlugin(ToolchainWalker.java:226) at de.uni_freiburg.informatik.ultimate.core.coreplugin.ToolchainWalker.walkUnprotected(ToolchainWalker.java:142) at de.uni_freiburg.informatik.ultimate.core.coreplugin.ToolchainWalker.walk(ToolchainWalker.java:104) at de.uni_freiburg.informatik.ultimate.core.coreplugin.ToolchainManager$Toolchain.processToolchain(ToolchainManager.java:320) at de.uni_freiburg.informatik.ultimate.core.coreplugin.toolchain.DefaultToolchainJob.run(DefaultToolchainJob.java:145) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63) [2020-11-07 02:20:27,884 INFO L168 Benchmark]: Toolchain (without parser) took 31429.75 ms. Allocated memory was 167.8 MB in the beginning and 518.0 MB in the end (delta: 350.2 MB). Free memory was 143.6 MB in the beginning and 197.3 MB in the end (delta: -53.7 MB). Peak memory consumption was 297.1 MB. Max. memory is 8.0 GB. [2020-11-07 02:20:27,884 INFO L168 Benchmark]: CDTParser took 0.21 ms. Allocated memory is still 167.8 MB. Free memory was 140.8 MB in the beginning and 140.7 MB in the end (delta: 102.3 kB). There was no memory consumed. Max. memory is 8.0 GB. [2020-11-07 02:20:27,885 INFO L168 Benchmark]: CACSL2BoogieTranslator took 334.65 ms. Allocated memory is still 167.8 MB. Free memory was 143.0 MB in the beginning and 130.7 MB in the end (delta: 12.3 MB). Peak memory consumption was 11.5 MB. Max. memory is 8.0 GB. [2020-11-07 02:20:27,886 INFO L168 Benchmark]: Boogie Preprocessor took 52.16 ms. Allocated memory is still 167.8 MB. Free memory was 130.7 MB in the beginning and 128.7 MB in the end (delta: 2.0 MB). Peak memory consumption was 2.1 MB. Max. memory is 8.0 GB. [2020-11-07 02:20:27,887 INFO L168 Benchmark]: RCFGBuilder took 814.27 ms. Allocated memory is still 167.8 MB. Free memory was 128.5 MB in the beginning and 128.1 MB in the end (delta: 464.5 kB). Peak memory consumption was 17.8 MB. Max. memory is 8.0 GB. [2020-11-07 02:20:27,888 INFO L168 Benchmark]: TraceAbstraction took 30216.32 ms. Allocated memory was 167.8 MB in the beginning and 518.0 MB in the end (delta: 350.2 MB). Free memory was 127.5 MB in the beginning and 197.3 MB in the end (delta: -69.8 MB). Peak memory consumption was 280.4 MB. Max. memory is 8.0 GB. [2020-11-07 02:20:27,891 INFO L339 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * CDTParser took 0.21 ms. Allocated memory is still 167.8 MB. Free memory was 140.8 MB in the beginning and 140.7 MB in the end (delta: 102.3 kB). There was no memory consumed. Max. memory is 8.0 GB. * CACSL2BoogieTranslator took 334.65 ms. Allocated memory is still 167.8 MB. Free memory was 143.0 MB in the beginning and 130.7 MB in the end (delta: 12.3 MB). Peak memory consumption was 11.5 MB. Max. memory is 8.0 GB. * Boogie Preprocessor took 52.16 ms. Allocated memory is still 167.8 MB. Free memory was 130.7 MB in the beginning and 128.7 MB in the end (delta: 2.0 MB). Peak memory consumption was 2.1 MB. Max. memory is 8.0 GB. * RCFGBuilder took 814.27 ms. Allocated memory is still 167.8 MB. Free memory was 128.5 MB in the beginning and 128.1 MB in the end (delta: 464.5 kB). Peak memory consumption was 17.8 MB. Max. memory is 8.0 GB. * TraceAbstraction took 30216.32 ms. Allocated memory was 167.8 MB in the beginning and 518.0 MB in the end (delta: 350.2 MB). Free memory was 127.5 MB in the beginning and 197.3 MB in the end (delta: -69.8 MB). Peak memory consumption was 280.4 MB. Max. memory is 8.0 GB. * Results from de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: - ExceptionOrErrorResult: NullPointerException: null de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: NullPointerException: null: de.uni_freiburg.informatik.ultimate.lib.acceleratedinterpolation.AcceleratedInterpolation.accelerateNestedLoops(AcceleratedInterpolation.java:569) RESULT: Ultimate could not prove your program: Toolchain returned no result. Received shutdown request...