./Ultimate.py --spec ../../sv-benchmarks/c/properties/unreach-call.prp --file ../../sv-benchmarks/c/recursive/Ackermann02.c --full-output --architecture 32bit -------------------------------------------------------------------------------- Checking for ERROR reachability Using default analysis Version a4ecdabc Calling Ultimate with: /usr/bin/java -Dosgi.configuration.area=/tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/data/config -Xmx15G -Xms4m -jar /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/plugins/org.eclipse.equinox.launcher_1.5.800.v20200727-1323.jar -data @noDefault -ultimatedata /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/data -tc /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/config/TaipanReach.xml -i ../../sv-benchmarks/c/recursive/Ackermann02.c -s /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/config/svcomp-Reach-32bit-Taipan_Default.epf --cacsl2boogietranslator.entry.function main --witnessprinter.witness.directory /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan --witnessprinter.witness.filename witness.graphml --witnessprinter.write.witness.besides.input.file false --witnessprinter.graph.data.specification CHECK( init(main()), LTL(G ! call(reach_error())) ) --witnessprinter.graph.data.producer Taipan --witnessprinter.graph.data.architecture 32bit --witnessprinter.graph.data.programhash 035ba3eae82c1904e7a9c5ede20dafeb782b642c ............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................. Execution finished normally Writing output log to file Ultimate.log Writing human readable error path to file UltimateCounterExample.errorpath Result: FALSE --- Real Ultimate output --- This is Ultimate 0.2.0-a4ecdab [2020-11-22 12:52:17,919 INFO L177 SettingsManager]: Resetting all preferences to default values... [2020-11-22 12:52:17,922 INFO L181 SettingsManager]: Resetting UltimateCore preferences to default values [2020-11-22 12:52:17,980 INFO L184 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2020-11-22 12:52:17,981 INFO L181 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2020-11-22 12:52:17,988 INFO L181 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2020-11-22 12:52:17,991 INFO L181 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2020-11-22 12:52:18,004 INFO L181 SettingsManager]: Resetting LassoRanker preferences to default values [2020-11-22 12:52:18,008 INFO L181 SettingsManager]: Resetting Reaching Definitions preferences to default values [2020-11-22 12:52:18,017 INFO L181 SettingsManager]: Resetting SyntaxChecker preferences to default values [2020-11-22 12:52:18,019 INFO L181 SettingsManager]: Resetting Sifa preferences to default values [2020-11-22 12:52:18,020 INFO L184 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2020-11-22 12:52:18,022 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2020-11-22 12:52:18,025 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2020-11-22 12:52:18,027 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2020-11-22 12:52:18,031 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2020-11-22 12:52:18,032 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2020-11-22 12:52:18,038 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2020-11-22 12:52:18,040 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2020-11-22 12:52:18,047 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2020-11-22 12:52:18,052 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2020-11-22 12:52:18,054 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2020-11-22 12:52:18,057 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2020-11-22 12:52:18,059 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2020-11-22 12:52:18,066 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... [2020-11-22 12:52:18,067 INFO L184 SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring... [2020-11-22 12:52:18,068 INFO L181 SettingsManager]: Resetting TreeAutomizer preferences to default values [2020-11-22 12:52:18,070 INFO L181 SettingsManager]: Resetting IcfgToChc preferences to default values [2020-11-22 12:52:18,071 INFO L181 SettingsManager]: Resetting IcfgTransformer preferences to default values [2020-11-22 12:52:18,073 INFO L184 SettingsManager]: ReqToTest provides no preferences, ignoring... [2020-11-22 12:52:18,073 INFO L181 SettingsManager]: Resetting Boogie Printer preferences to default values [2020-11-22 12:52:18,075 INFO L181 SettingsManager]: Resetting ChcSmtPrinter preferences to default values [2020-11-22 12:52:18,077 INFO L181 SettingsManager]: Resetting ReqPrinter preferences to default values [2020-11-22 12:52:18,079 INFO L181 SettingsManager]: Resetting Witness Printer preferences to default values [2020-11-22 12:52:18,080 INFO L184 SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring... [2020-11-22 12:52:18,081 INFO L181 SettingsManager]: Resetting CDTParser preferences to default values [2020-11-22 12:52:18,082 INFO L184 SettingsManager]: AutomataScriptParser provides no preferences, ignoring... [2020-11-22 12:52:18,082 INFO L184 SettingsManager]: ReqParser provides no preferences, ignoring... [2020-11-22 12:52:18,082 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2020-11-22 12:52:18,084 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2020-11-22 12:52:18,084 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2020-11-22 12:52:18,088 INFO L101 SettingsManager]: Beginning loading settings from /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/config/svcomp-Reach-32bit-Taipan_Default.epf [2020-11-22 12:52:18,141 INFO L113 SettingsManager]: Loading preferences was successful [2020-11-22 12:52:18,142 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2020-11-22 12:52:18,143 INFO L136 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2020-11-22 12:52:18,143 INFO L138 SettingsManager]: * User list type=DISABLED [2020-11-22 12:52:18,144 INFO L136 SettingsManager]: Preferences of Abstract Interpretation differ from their defaults: [2020-11-22 12:52:18,144 INFO L138 SettingsManager]: * Explicit value domain=true [2020-11-22 12:52:18,144 INFO L138 SettingsManager]: * Abstract domain for RCFG-of-the-future=PoormanAbstractDomain [2020-11-22 12:52:18,145 INFO L138 SettingsManager]: * Octagon Domain=false [2020-11-22 12:52:18,145 INFO L138 SettingsManager]: * Abstract domain=CompoundDomain [2020-11-22 12:52:18,145 INFO L138 SettingsManager]: * Check feasibility of abstract posts with an SMT solver=true [2020-11-22 12:52:18,147 INFO L138 SettingsManager]: * Use the RCFG-of-the-future interface=true [2020-11-22 12:52:18,147 INFO L138 SettingsManager]: * Interval Domain=false [2020-11-22 12:52:18,147 INFO L136 SettingsManager]: Preferences of Sifa differ from their defaults: [2020-11-22 12:52:18,148 INFO L138 SettingsManager]: * Call Summarizer=TopInputCallSummarizer [2020-11-22 12:52:18,148 INFO L138 SettingsManager]: * Simplification Technique=SIMPLIFY_QUICK [2020-11-22 12:52:18,150 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2020-11-22 12:52:18,150 INFO L138 SettingsManager]: * sizeof long=4 [2020-11-22 12:52:18,150 INFO L138 SettingsManager]: * Overapproximate operations on floating types=true [2020-11-22 12:52:18,150 INFO L138 SettingsManager]: * sizeof POINTER=4 [2020-11-22 12:52:18,151 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2020-11-22 12:52:18,151 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2020-11-22 12:52:18,151 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2020-11-22 12:52:18,152 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2020-11-22 12:52:18,152 INFO L138 SettingsManager]: * Adapt memory model on pointer casts if necessary=true [2020-11-22 12:52:18,152 INFO L138 SettingsManager]: * sizeof long double=12 [2020-11-22 12:52:18,153 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2020-11-22 12:52:18,153 INFO L138 SettingsManager]: * Use constant arrays=true [2020-11-22 12:52:18,153 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2020-11-22 12:52:18,154 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2020-11-22 12:52:18,155 INFO L138 SettingsManager]: * To the following directory=./dump/ [2020-11-22 12:52:18,156 INFO L138 SettingsManager]: * SMT solver=External_DefaultMode [2020-11-22 12:52:18,156 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2020-11-22 12:52:18,157 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2020-11-22 12:52:18,157 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2020-11-22 12:52:18,157 INFO L138 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2020-11-22 12:52:18,157 INFO L138 SettingsManager]: * Trace refinement strategy=SIFA_TAIPAN [2020-11-22 12:52:18,158 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2020-11-22 12:52:18,158 INFO L138 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2020-11-22 12:52:18,158 INFO L138 SettingsManager]: * Trace refinement exception blacklist=NONE [2020-11-22 12:52:18,159 INFO L138 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2020-11-22 12:52:18,159 INFO L138 SettingsManager]: * Abstract interpretation Mode=USE_PREDICATES WARNING: An illegal reflective access operation has occurred WARNING: Illegal reflective access by com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 (file:/tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/plugins/com.sun.xml.bind_2.2.0.v201505121915.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int) WARNING: Please consider reporting this to the maintainers of com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations WARNING: All illegal access operations will be denied in a future release Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator: Entry function -> main Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness directory -> /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness filename -> witness.graphml Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Write witness besides input file -> false Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data specification -> CHECK( init(main()), LTL(G ! call(reach_error())) ) Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data producer -> Taipan Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data architecture -> 32bit Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data programhash -> 035ba3eae82c1904e7a9c5ede20dafeb782b642c [2020-11-22 12:52:18,474 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2020-11-22 12:52:18,526 INFO L261 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2020-11-22 12:52:18,529 INFO L217 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2020-11-22 12:52:18,530 INFO L271 PluginConnector]: Initializing CDTParser... [2020-11-22 12:52:18,534 INFO L275 PluginConnector]: CDTParser initialized [2020-11-22 12:52:18,535 INFO L432 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/../../sv-benchmarks/c/recursive/Ackermann02.c [2020-11-22 12:52:18,620 INFO L220 CDTParser]: Created temporary CDT project at /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/data/273f8b29e/2c9ba75b64ff4d4c8ca901a4e1d100cc/FLAGd080fccaf [2020-11-22 12:52:19,171 INFO L306 CDTParser]: Found 1 translation units. [2020-11-22 12:52:19,172 INFO L160 CDTParser]: Scanning /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/sv-benchmarks/c/recursive/Ackermann02.c [2020-11-22 12:52:19,178 INFO L349 CDTParser]: About to delete temporary CDT project at /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/data/273f8b29e/2c9ba75b64ff4d4c8ca901a4e1d100cc/FLAGd080fccaf [2020-11-22 12:52:19,516 INFO L357 CDTParser]: Successfully deleted /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/data/273f8b29e/2c9ba75b64ff4d4c8ca901a4e1d100cc [2020-11-22 12:52:19,519 INFO L299 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2020-11-22 12:52:19,521 INFO L131 ToolchainWalker]: Walking toolchain with 6 elements. [2020-11-22 12:52:19,524 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2020-11-22 12:52:19,524 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2020-11-22 12:52:19,528 INFO L275 PluginConnector]: CACSL2BoogieTranslator initialized [2020-11-22 12:52:19,529 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,531 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@48ce3c0f and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19, skipping insertion in model container [2020-11-22 12:52:19,532 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,540 INFO L145 MainTranslator]: Starting translation in SV-COMP mode [2020-11-22 12:52:19,553 INFO L178 MainTranslator]: Built tables and reachable declarations [2020-11-22 12:52:19,734 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-11-22 12:52:19,743 INFO L203 MainTranslator]: Completed pre-run [2020-11-22 12:52:19,759 INFO L206 PostProcessor]: Analyzing one entry point: main [2020-11-22 12:52:19,773 INFO L208 MainTranslator]: Completed translation [2020-11-22 12:52:19,774 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19 WrapperNode [2020-11-22 12:52:19,774 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2020-11-22 12:52:19,775 INFO L113 PluginConnector]: ------------------------Boogie Procedure Inliner---------------------------- [2020-11-22 12:52:19,776 INFO L271 PluginConnector]: Initializing Boogie Procedure Inliner... [2020-11-22 12:52:19,776 INFO L275 PluginConnector]: Boogie Procedure Inliner initialized [2020-11-22 12:52:19,784 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,790 INFO L185 PluginConnector]: Executing the observer Inliner from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,806 INFO L132 PluginConnector]: ------------------------ END Boogie Procedure Inliner---------------------------- [2020-11-22 12:52:19,807 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2020-11-22 12:52:19,808 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2020-11-22 12:52:19,808 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2020-11-22 12:52:19,816 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,816 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,818 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,818 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,822 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,824 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,825 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... [2020-11-22 12:52:19,827 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2020-11-22 12:52:19,828 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2020-11-22 12:52:19,829 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2020-11-22 12:52:19,829 INFO L275 PluginConnector]: RCFGBuilder initialized [2020-11-22 12:52:19,830 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (1/1) ... No working directory specified, using /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/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 [2020-11-22 12:52:19,916 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2020-11-22 12:52:19,916 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2020-11-22 12:52:19,916 INFO L130 BoogieDeclarations]: Found specification of procedure ackermann [2020-11-22 12:52:19,917 INFO L138 BoogieDeclarations]: Found implementation of procedure ackermann [2020-11-22 12:52:19,917 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int [2020-11-22 12:52:19,917 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocOnStack [2020-11-22 12:52:20,314 INFO L293 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2020-11-22 12:52:20,314 INFO L298 CfgBuilder]: Removed 6 assume(true) statements. [2020-11-22 12:52:20,316 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 22.11 12:52:20 BoogieIcfgContainer [2020-11-22 12:52:20,317 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2020-11-22 12:52:20,319 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2020-11-22 12:52:20,319 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2020-11-22 12:52:20,333 INFO L275 PluginConnector]: TraceAbstraction initialized [2020-11-22 12:52:20,348 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 22.11 12:52:19" (1/3) ... [2020-11-22 12:52:20,349 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@594f05be and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 22.11 12:52:20, skipping insertion in model container [2020-11-22 12:52:20,350 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 22.11 12:52:19" (2/3) ... [2020-11-22 12:52:20,350 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@594f05be and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 22.11 12:52:20, skipping insertion in model container [2020-11-22 12:52:20,350 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 22.11 12:52:20" (3/3) ... [2020-11-22 12:52:20,352 INFO L111 eAbstractionObserver]: Analyzing ICFG Ackermann02.c [2020-11-22 12:52:20,364 INFO L164 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2020-11-22 12:52:20,372 INFO L176 ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations. [2020-11-22 12:52:20,384 INFO L253 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2020-11-22 12:52:20,413 INFO L377 AbstractCegarLoop]: Interprodecural is true [2020-11-22 12:52:20,414 INFO L378 AbstractCegarLoop]: Hoare is true [2020-11-22 12:52:20,414 INFO L379 AbstractCegarLoop]: Compute interpolants for FPandBP [2020-11-22 12:52:20,414 INFO L380 AbstractCegarLoop]: Backedges is STRAIGHT_LINE [2020-11-22 12:52:20,414 INFO L381 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2020-11-22 12:52:20,415 INFO L382 AbstractCegarLoop]: Difference is false [2020-11-22 12:52:20,415 INFO L383 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2020-11-22 12:52:20,415 INFO L387 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2020-11-22 12:52:20,434 INFO L276 IsEmpty]: Start isEmpty. Operand 21 states. [2020-11-22 12:52:20,439 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 12 [2020-11-22 12:52:20,439 INFO L414 BasicCegarLoop]: Found error trace [2020-11-22 12:52:20,440 INFO L422 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-11-22 12:52:20,441 INFO L429 AbstractCegarLoop]: === Iteration 1 === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-22 12:52:20,446 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-22 12:52:20,446 INFO L82 PathProgramCache]: Analyzing trace with hash -1030206601, now seen corresponding path program 1 times [2020-11-22 12:52:20,456 INFO L162 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2020-11-22 12:52:20,456 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [464044025] [2020-11-22 12:52:20,457 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-22 12:52:20,570 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-22 12:52:20,681 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2020-11-22 12:52:20,682 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [464044025] [2020-11-22 12:52:20,683 INFO L219 FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2020-11-22 12:52:20,683 INFO L232 FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2020-11-22 12:52:20,684 INFO L155 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1424265109] [2020-11-22 12:52:20,689 INFO L461 AbstractCegarLoop]: Interpolant automaton has 5 states [2020-11-22 12:52:20,689 INFO L142 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2020-11-22 12:52:20,702 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2020-11-22 12:52:20,703 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2020-11-22 12:52:20,705 INFO L87 Difference]: Start difference. First operand 21 states. Second operand 5 states. [2020-11-22 12:52:20,910 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-11-22 12:52:20,911 INFO L93 Difference]: Finished difference Result 34 states and 45 transitions. [2020-11-22 12:52:20,912 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2020-11-22 12:52:20,913 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 11 [2020-11-22 12:52:20,914 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-11-22 12:52:20,929 INFO L225 Difference]: With dead ends: 34 [2020-11-22 12:52:20,930 INFO L226 Difference]: Without dead ends: 24 [2020-11-22 12:52:20,935 INFO L677 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 [2020-11-22 12:52:20,955 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 24 states. [2020-11-22 12:52:20,990 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 24 to 24. [2020-11-22 12:52:20,991 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 24 states. [2020-11-22 12:52:20,997 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 24 states to 24 states and 32 transitions. [2020-11-22 12:52:20,998 INFO L78 Accepts]: Start accepts. Automaton has 24 states and 32 transitions. Word has length 11 [2020-11-22 12:52:20,999 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-11-22 12:52:20,999 INFO L481 AbstractCegarLoop]: Abstraction has 24 states and 32 transitions. [2020-11-22 12:52:20,999 INFO L482 AbstractCegarLoop]: Interpolant automaton has 5 states. [2020-11-22 12:52:20,999 INFO L276 IsEmpty]: Start isEmpty. Operand 24 states and 32 transitions. [2020-11-22 12:52:21,004 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 19 [2020-11-22 12:52:21,004 INFO L414 BasicCegarLoop]: Found error trace [2020-11-22 12:52:21,005 INFO L422 BasicCegarLoop]: trace histogram [2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-11-22 12:52:21,006 WARN L518 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2020-11-22 12:52:21,008 INFO L429 AbstractCegarLoop]: === Iteration 2 === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-22 12:52:21,012 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-22 12:52:21,012 INFO L82 PathProgramCache]: Analyzing trace with hash 1585564691, now seen corresponding path program 1 times [2020-11-22 12:52:21,012 INFO L162 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2020-11-22 12:52:21,013 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [156219684] [2020-11-22 12:52:21,013 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-22 12:52:21,053 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-22 12:52:21,133 INFO L134 CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 2 refuted. 0 times theorem prover too weak. 2 trivial. 0 not checked. [2020-11-22 12:52:21,134 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [156219684] [2020-11-22 12:52:21,134 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [276890798] [2020-11-22 12:52:21,134 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY No working directory specified, using /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/z3 Starting monitored process 2 with z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 2 with z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-11-22 12:52:21,248 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-22 12:52:21,264 INFO L263 TraceCheckSpWp]: Trace formula consists of 85 conjuncts, 6 conjunts are in the unsatisfiable core [2020-11-22 12:52:21,270 INFO L286 TraceCheckSpWp]: Computing forward predicates... [2020-11-22 12:52:21,356 INFO L134 CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 2 refuted. 0 times theorem prover too weak. 2 trivial. 0 not checked. [2020-11-22 12:52:21,357 INFO L328 TraceCheckSpWp]: Computing backward predicates... [2020-11-22 12:52:21,615 INFO L603 QuantifierPusher]: Distributing 2 disjuncts over 2 conjuncts [2020-11-22 12:52:21,640 INFO L603 QuantifierPusher]: Distributing 2 disjuncts over 2 conjuncts [2020-11-22 12:52:21,724 INFO L134 CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 3 refuted. 0 times theorem prover too weak. 1 trivial. 0 not checked. [2020-11-22 12:52:21,724 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSifa [1518740823] [2020-11-22 12:52:21,775 INFO L159 IcfgInterpreter]: Started Sifa with 15 locations of interest [2020-11-22 12:52:21,776 INFO L166 IcfgInterpreter]: Building call graph [2020-11-22 12:52:21,784 FATAL L? ?]: Ignoring exception! java.lang.IllegalArgumentException: Recursive programs are not supported. at de.uni_freiburg.informatik.ultimate.lib.sifa.CallGraph.topsortRelevant(CallGraph.java:132) at de.uni_freiburg.informatik.ultimate.lib.sifa.CallGraph.(CallGraph.java:97) at de.uni_freiburg.informatik.ultimate.lib.sifa.IcfgInterpreter.(IcfgInterpreter.java:92) at de.uni_freiburg.informatik.ultimate.plugins.sifa.SifaBuilder.construct(SifaBuilder.java:94) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.SifaRunner.(SifaRunner.java:98) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.IpTcStrategyModuleSifa.construct(IpTcStrategyModuleSifa.java:67) 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.getInterpolantComputationStatus(IpTcStrategyModuleBase.java:76) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.tryExecuteInterpolantGenerator(AutomatonFreeRefinementEngine.java:289) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.generateProof(AutomatonFreeRefinementEngine.java:189) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.executeStrategy(AutomatonFreeRefinementEngine.java:179) 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:341) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionStarter.runCegarLoops(TraceAbstractionStarter.java:182) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionStarter.(TraceAbstractionStarter.java:134) 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) [2020-11-22 12:52:21,796 INFO L219 FreeRefinementEngine]: Constructing automaton from 0 perfect and 3 imperfect interpolant sequences. [2020-11-22 12:52:21,797 INFO L232 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [6, 6, 7] total 8 [2020-11-22 12:52:21,798 INFO L155 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1556964980] [2020-11-22 12:52:21,800 INFO L461 AbstractCegarLoop]: Interpolant automaton has 8 states [2020-11-22 12:52:21,800 INFO L142 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2020-11-22 12:52:21,803 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 8 interpolants. [2020-11-22 12:52:21,804 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=19, Invalid=37, Unknown=0, NotChecked=0, Total=56 [2020-11-22 12:52:21,804 INFO L87 Difference]: Start difference. First operand 24 states and 32 transitions. Second operand 8 states. [2020-11-22 12:52:22,001 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-11-22 12:52:22,002 INFO L93 Difference]: Finished difference Result 34 states and 48 transitions. [2020-11-22 12:52:22,003 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 6 states. [2020-11-22 12:52:22,003 INFO L78 Accepts]: Start accepts. Automaton has 8 states. Word has length 18 [2020-11-22 12:52:22,003 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-11-22 12:52:22,005 INFO L225 Difference]: With dead ends: 34 [2020-11-22 12:52:22,005 INFO L226 Difference]: Without dead ends: 30 [2020-11-22 12:52:22,007 INFO L677 BasicCegarLoop]: 0 DeclaredPredicates, 43 GetRequests, 32 SyntacticMatches, 3 SemanticMatches, 8 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 4 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=33, Invalid=57, Unknown=0, NotChecked=0, Total=90 [2020-11-22 12:52:22,007 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 30 states. [2020-11-22 12:52:22,023 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 30 to 30. [2020-11-22 12:52:22,023 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 30 states. [2020-11-22 12:52:22,025 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 30 states to 30 states and 44 transitions. [2020-11-22 12:52:22,026 INFO L78 Accepts]: Start accepts. Automaton has 30 states and 44 transitions. Word has length 18 [2020-11-22 12:52:22,026 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-11-22 12:52:22,026 INFO L481 AbstractCegarLoop]: Abstraction has 30 states and 44 transitions. [2020-11-22 12:52:22,026 INFO L482 AbstractCegarLoop]: Interpolant automaton has 8 states. [2020-11-22 12:52:22,027 INFO L276 IsEmpty]: Start isEmpty. Operand 30 states and 44 transitions. [2020-11-22 12:52:22,029 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 26 [2020-11-22 12:52:22,029 INFO L414 BasicCegarLoop]: Found error trace [2020-11-22 12:52:22,030 INFO L422 BasicCegarLoop]: trace histogram [3, 3, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-11-22 12:52:22,244 WARN L518 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 2 z3 -smt2 -in SMTLIB2_COMPLIANT=true,SelfDestructingSolverStorable1 [2020-11-22 12:52:22,244 INFO L429 AbstractCegarLoop]: === Iteration 3 === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-22 12:52:22,244 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-22 12:52:22,245 INFO L82 PathProgramCache]: Analyzing trace with hash -1150060871, now seen corresponding path program 2 times [2020-11-22 12:52:22,245 INFO L162 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2020-11-22 12:52:22,245 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1503130648] [2020-11-22 12:52:22,245 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-22 12:52:22,294 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2020-11-22 12:52:22,348 INFO L134 CoverageAnalysis]: Checked inductivity of 15 backedges. 10 proven. 1 refuted. 0 times theorem prover too weak. 4 trivial. 0 not checked. [2020-11-22 12:52:22,349 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1503130648] [2020-11-22 12:52:22,349 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleZ3 [1063973131] [2020-11-22 12:52:22,349 INFO L93 rtionOrderModulation]: Changing assertion order to OUTSIDE_LOOP_FIRST2 No working directory specified, using /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/z3 Starting monitored process 3 with z3 -smt2 -in SMTLIB2_COMPLIANT=true (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 3 with z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-11-22 12:52:22,411 INFO L228 tOrderPrioritization]: Assert order OUTSIDE_LOOP_FIRST2 issued 3 check-sat command(s) [2020-11-22 12:52:22,411 INFO L229 tOrderPrioritization]: Conjunction of SSA is unsat [2020-11-22 12:52:22,414 INFO L263 TraceCheckSpWp]: Trace formula consists of 105 conjuncts, 3 conjunts are in the unsatisfiable core [2020-11-22 12:52:22,417 INFO L286 TraceCheckSpWp]: Computing forward predicates... [2020-11-22 12:52:22,452 INFO L134 CoverageAnalysis]: Checked inductivity of 15 backedges. 10 proven. 1 refuted. 0 times theorem prover too weak. 4 trivial. 0 not checked. [2020-11-22 12:52:22,452 INFO L328 TraceCheckSpWp]: Computing backward predicates... [2020-11-22 12:52:22,532 INFO L134 CoverageAnalysis]: Checked inductivity of 15 backedges. 10 proven. 1 refuted. 0 times theorem prover too weak. 4 trivial. 0 not checked. [2020-11-22 12:52:22,532 INFO L353 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSifa [210033216] [2020-11-22 12:52:22,543 INFO L159 IcfgInterpreter]: Started Sifa with 15 locations of interest [2020-11-22 12:52:22,544 INFO L166 IcfgInterpreter]: Building call graph [2020-11-22 12:52:22,544 FATAL L? ?]: Ignoring exception! java.lang.IllegalArgumentException: Recursive programs are not supported. at de.uni_freiburg.informatik.ultimate.lib.sifa.CallGraph.topsortRelevant(CallGraph.java:132) at de.uni_freiburg.informatik.ultimate.lib.sifa.CallGraph.(CallGraph.java:97) at de.uni_freiburg.informatik.ultimate.lib.sifa.IcfgInterpreter.(IcfgInterpreter.java:92) at de.uni_freiburg.informatik.ultimate.plugins.sifa.SifaBuilder.construct(SifaBuilder.java:94) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.SifaRunner.(SifaRunner.java:98) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.IpTcStrategyModuleSifa.construct(IpTcStrategyModuleSifa.java:67) 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.getInterpolantComputationStatus(IpTcStrategyModuleBase.java:76) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.tryExecuteInterpolantGenerator(AutomatonFreeRefinementEngine.java:289) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.generateProof(AutomatonFreeRefinementEngine.java:189) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.tracehandling.AutomatonFreeRefinementEngine.executeStrategy(AutomatonFreeRefinementEngine.java:179) 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:341) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionStarter.runCegarLoops(TraceAbstractionStarter.java:182) at de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionStarter.(TraceAbstractionStarter.java:134) 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) [2020-11-22 12:52:22,544 INFO L219 FreeRefinementEngine]: Constructing automaton from 0 perfect and 3 imperfect interpolant sequences. [2020-11-22 12:52:22,544 INFO L232 FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [4, 4, 4] total 7 [2020-11-22 12:52:22,545 INFO L155 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [257024089] [2020-11-22 12:52:22,545 INFO L461 AbstractCegarLoop]: Interpolant automaton has 7 states [2020-11-22 12:52:22,545 INFO L142 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy SIFA_TAIPAN [2020-11-22 12:52:22,546 INFO L142 InterpolantAutomaton]: Constructing interpolant automaton starting with 7 interpolants. [2020-11-22 12:52:22,546 INFO L144 InterpolantAutomaton]: CoverageRelationStatistics Valid=17, Invalid=25, Unknown=0, NotChecked=0, Total=42 [2020-11-22 12:52:22,546 INFO L87 Difference]: Start difference. First operand 30 states and 44 transitions. Second operand 7 states. [2020-11-22 12:52:22,633 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2020-11-22 12:52:22,633 INFO L93 Difference]: Finished difference Result 60 states and 112 transitions. [2020-11-22 12:52:22,636 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2020-11-22 12:52:22,636 INFO L78 Accepts]: Start accepts. Automaton has 7 states. Word has length 25 [2020-11-22 12:52:22,636 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2020-11-22 12:52:22,639 INFO L225 Difference]: With dead ends: 60 [2020-11-22 12:52:22,639 INFO L226 Difference]: Without dead ends: 34 [2020-11-22 12:52:22,643 INFO L677 BasicCegarLoop]: 0 DeclaredPredicates, 54 GetRequests, 46 SyntacticMatches, 2 SemanticMatches, 6 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 2 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=24, Invalid=32, Unknown=0, NotChecked=0, Total=56 [2020-11-22 12:52:22,645 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 34 states. [2020-11-22 12:52:22,657 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 34 to 34. [2020-11-22 12:52:22,657 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 34 states. [2020-11-22 12:52:22,662 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 34 states to 34 states and 55 transitions. [2020-11-22 12:52:22,663 INFO L78 Accepts]: Start accepts. Automaton has 34 states and 55 transitions. Word has length 25 [2020-11-22 12:52:22,664 INFO L84 Accepts]: Finished accepts. word is rejected. [2020-11-22 12:52:22,664 INFO L481 AbstractCegarLoop]: Abstraction has 34 states and 55 transitions. [2020-11-22 12:52:22,664 INFO L482 AbstractCegarLoop]: Interpolant automaton has 7 states. [2020-11-22 12:52:22,664 INFO L276 IsEmpty]: Start isEmpty. Operand 34 states and 55 transitions. [2020-11-22 12:52:22,672 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 39 [2020-11-22 12:52:22,674 INFO L414 BasicCegarLoop]: Found error trace [2020-11-22 12:52:22,675 INFO L422 BasicCegarLoop]: trace histogram [5, 5, 3, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2020-11-22 12:52:22,896 WARN L518 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable2,3 z3 -smt2 -in SMTLIB2_COMPLIANT=true [2020-11-22 12:52:22,896 INFO L429 AbstractCegarLoop]: === Iteration 4 === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION]=== [2020-11-22 12:52:22,897 INFO L144 PredicateUnifier]: Initialized classic predicate unifier [2020-11-22 12:52:22,897 INFO L82 PathProgramCache]: Analyzing trace with hash -502755874, now seen corresponding path program 1 times [2020-11-22 12:52:22,897 INFO L162 FreeRefinementEngine]: Executing refinement strategy SIFA_TAIPAN [2020-11-22 12:52:22,898 INFO L353 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [144221204] [2020-11-22 12:52:22,898 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2020-11-22 12:52:22,952 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is sat [2020-11-22 12:52:22,955 INFO L221 TraceCheck]: Trace is feasible, we will do another trace check, this time with branch encoders. [2020-11-22 12:52:22,985 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is sat [2020-11-22 12:52:22,986 INFO L221 TraceCheck]: Trace is feasible, we will do another trace check, this time with branch encoders. [2020-11-22 12:52:23,015 INFO L173 FreeRefinementEngine]: Strategy SIFA_TAIPAN found a feasible trace [2020-11-22 12:52:23,015 INFO L523 BasicCegarLoop]: Counterexample might be feasible [2020-11-22 12:52:23,015 WARN L518 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3 [2020-11-22 12:52:23,063 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction CFG 22.11 12:52:23 BoogieIcfgContainer [2020-11-22 12:52:23,063 INFO L132 PluginConnector]: ------------------------ END TraceAbstraction---------------------------- [2020-11-22 12:52:23,064 INFO L113 PluginConnector]: ------------------------Witness Printer---------------------------- [2020-11-22 12:52:23,064 INFO L271 PluginConnector]: Initializing Witness Printer... [2020-11-22 12:52:23,065 INFO L275 PluginConnector]: Witness Printer initialized [2020-11-22 12:52:23,065 INFO L185 PluginConnector]: Executing the observer RCFGCatcher from plugin Witness Printer for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 22.11 12:52:20" (3/4) ... [2020-11-22 12:52:23,067 INFO L131 WitnessPrinter]: Generating witness for reachability counterexample [2020-11-22 12:52:23,127 INFO L141 WitnessManager]: Wrote witness to /tmp/vcloud-vcloud-master/worker/run_dir_6d3f4243-d94c-4e1e-92a1-c425166474bb/bin/utaipan/witness.graphml [2020-11-22 12:52:23,127 INFO L132 PluginConnector]: ------------------------ END Witness Printer---------------------------- [2020-11-22 12:52:23,129 INFO L168 Benchmark]: Toolchain (without parser) took 3607.42 ms. Allocated memory was 79.7 MB in the beginning and 98.6 MB in the end (delta: 18.9 MB). Free memory was 46.4 MB in the beginning and 56.9 MB in the end (delta: -10.5 MB). Peak memory consumption was 8.7 MB. Max. memory is 16.1 GB. [2020-11-22 12:52:23,130 INFO L168 Benchmark]: CDTParser took 0.29 ms. Allocated memory is still 79.7 MB. Free memory was 62.5 MB in the beginning and 62.3 MB in the end (delta: 130.6 kB). There was no memory consumed. Max. memory is 16.1 GB. [2020-11-22 12:52:23,131 INFO L168 Benchmark]: CACSL2BoogieTranslator took 250.71 ms. Allocated memory was 79.7 MB in the beginning and 98.6 MB in the end (delta: 18.9 MB). Free memory was 46.1 MB in the beginning and 77.4 MB in the end (delta: -31.3 MB). Peak memory consumption was 10.5 MB. Max. memory is 16.1 GB. [2020-11-22 12:52:23,132 INFO L168 Benchmark]: Boogie Procedure Inliner took 31.32 ms. Allocated memory is still 98.6 MB. Free memory was 77.4 MB in the beginning and 76.0 MB in the end (delta: 1.4 MB). There was no memory consumed. Max. memory is 16.1 GB. [2020-11-22 12:52:23,132 INFO L168 Benchmark]: Boogie Preprocessor took 19.97 ms. Allocated memory is still 98.6 MB. Free memory was 76.0 MB in the beginning and 75.0 MB in the end (delta: 1.0 MB). Peak memory consumption was 2.1 MB. Max. memory is 16.1 GB. [2020-11-22 12:52:23,133 INFO L168 Benchmark]: RCFGBuilder took 488.62 ms. Allocated memory is still 98.6 MB. Free memory was 75.0 MB in the beginning and 60.6 MB in the end (delta: 14.3 MB). Peak memory consumption was 14.7 MB. Max. memory is 16.1 GB. [2020-11-22 12:52:23,134 INFO L168 Benchmark]: TraceAbstraction took 2745.10 ms. Allocated memory is still 98.6 MB. Free memory was 60.3 MB in the beginning and 60.4 MB in the end (delta: -99.8 kB). Peak memory consumption was 984.1 kB. Max. memory is 16.1 GB. [2020-11-22 12:52:23,134 INFO L168 Benchmark]: Witness Printer took 63.40 ms. Allocated memory is still 98.6 MB. Free memory was 60.4 MB in the beginning and 56.9 MB in the end (delta: 3.5 MB). Peak memory consumption was 4.2 MB. Max. memory is 16.1 GB. [2020-11-22 12:52:23,138 INFO L339 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * CDTParser took 0.29 ms. Allocated memory is still 79.7 MB. Free memory was 62.5 MB in the beginning and 62.3 MB in the end (delta: 130.6 kB). There was no memory consumed. Max. memory is 16.1 GB. * CACSL2BoogieTranslator took 250.71 ms. Allocated memory was 79.7 MB in the beginning and 98.6 MB in the end (delta: 18.9 MB). Free memory was 46.1 MB in the beginning and 77.4 MB in the end (delta: -31.3 MB). Peak memory consumption was 10.5 MB. Max. memory is 16.1 GB. * Boogie Procedure Inliner took 31.32 ms. Allocated memory is still 98.6 MB. Free memory was 77.4 MB in the beginning and 76.0 MB in the end (delta: 1.4 MB). There was no memory consumed. Max. memory is 16.1 GB. * Boogie Preprocessor took 19.97 ms. Allocated memory is still 98.6 MB. Free memory was 76.0 MB in the beginning and 75.0 MB in the end (delta: 1.0 MB). Peak memory consumption was 2.1 MB. Max. memory is 16.1 GB. * RCFGBuilder took 488.62 ms. Allocated memory is still 98.6 MB. Free memory was 75.0 MB in the beginning and 60.6 MB in the end (delta: 14.3 MB). Peak memory consumption was 14.7 MB. Max. memory is 16.1 GB. * TraceAbstraction took 2745.10 ms. Allocated memory is still 98.6 MB. Free memory was 60.3 MB in the beginning and 60.4 MB in the end (delta: -99.8 kB). Peak memory consumption was 984.1 kB. Max. memory is 16.1 GB. * Witness Printer took 63.40 ms. Allocated memory is still 98.6 MB. Free memory was 60.4 MB in the beginning and 56.9 MB in the end (delta: 3.5 MB). Peak memory consumption was 4.2 MB. Max. memory is 16.1 GB. * Results from de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: - CounterExampleResult [Line: 3]: a call of __VERIFIER_error() is reachable a call of __VERIFIER_error() is reachable We found a FailurePath: [L28] int m = __VERIFIER_nondet_int(); [L29] COND FALSE !(m < 0 || m > 3) [L34] int n = __VERIFIER_nondet_int(); [L35] COND FALSE !(n < 0 || n > 23) [L41] CALL, EXPR ackermann(m,n) VAL [\old(m)=2, \old(n)=0] [L17] COND FALSE !(m==0) VAL [\old(m)=2, \old(n)=0, m=2, n=0] [L20] COND TRUE n==0 VAL [\old(m)=2, \old(n)=0, m=2, n=0] [L21] CALL, EXPR ackermann(m-1,1) VAL [\old(m)=1, \old(n)=1] [L17] COND FALSE !(m==0) VAL [\old(m)=1, \old(n)=1, m=1, n=1] [L20] COND FALSE !(n==0) VAL [\old(m)=1, \old(n)=1, m=1, n=1] [L23] CALL, EXPR ackermann(m,n-1) VAL [\old(m)=1, \old(n)=0] [L17] COND FALSE !(m==0) VAL [\old(m)=1, \old(n)=0, m=1, n=0] [L20] COND TRUE n==0 VAL [\old(m)=1, \old(n)=0, m=1, n=0] [L21] CALL, EXPR ackermann(m-1,1) VAL [\old(m)=0, \old(n)=1] [L17] COND TRUE m==0 [L18] return n+1; VAL [\old(m)=0, \old(n)=1, \result=2, m=0, n=1] [L21] RET, EXPR ackermann(m-1,1) VAL [\old(m)=1, \old(n)=0, ackermann(m-1,1)=2, m=1, n=0] [L21] return ackermann(m-1,1); [L23] RET, EXPR ackermann(m,n-1) VAL [\old(m)=1, \old(n)=1, ackermann(m,n-1)=2, m=1, n=1] [L23] CALL, EXPR ackermann(m-1,ackermann(m,n-1)) VAL [\old(m)=0, \old(n)=2] [L17] COND TRUE m==0 [L18] return n+1; VAL [\old(m)=0, \old(n)=2, \result=3, m=0, n=2] [L23] RET, EXPR ackermann(m-1,ackermann(m,n-1)) VAL [\old(m)=1, \old(n)=1, ackermann(m,n-1)=2, ackermann(m-1,ackermann(m,n-1))=3, m=1, n=1] [L23] return ackermann(m-1,ackermann(m,n-1)); [L21] RET, EXPR ackermann(m-1,1) VAL [\old(m)=2, \old(n)=0, ackermann(m-1,1)=3, m=2, n=0] [L21] return ackermann(m-1,1); [L41] RET, EXPR ackermann(m,n) [L41] int result = ackermann(m,n); [L42] COND FALSE !(m < 2 || result >= 4) [L3] __assert_fail("0", "Ackermann02.c", 3, "reach_error") - StatisticsResult: Ultimate Automizer benchmark data CFG has 2 procedures, 21 locations, 1 error locations. Started 1 CEGAR loops. VerificationResult: UNSAFE, OverallTime: 2.6s, OverallIterations: 4, TraceHistogramMax: 5, AutomataDifference: 0.5s, DeadEndRemovalTime: 0.0s, HoareAnnotationTime: 0.0s, InitialAbstractionConstructionTime: 0.0s, HoareTripleCheckerStatistics: 57 SDtfs, 70 SDslu, 96 SDs, 0 SdLazy, 116 SolverSat, 55 SolverUnsat, 0 SolverUnknown, 0 SolverNotchecked, 0.2s Time, PredicateUnifierStatistics: 0 DeclaredPredicates, 103 GetRequests, 80 SyntacticMatches, 5 SemanticMatches, 18 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 6 ImplicationChecksByTransitivity, 0.2s Time, 0.0s BasicInterpolantAutomatonTime, BiggestAbstraction: size=34occurred in iteration=3, traceCheckStatistics: No data available, InterpolantConsolidationStatistics: No data available, PathInvariantsStatistics: No data available, 0/0 InterpolantCoveringCapability, TotalInterpolationStatistics: No data available, 0.0s DumpTime, AutomataMinimizationStatistics: 0.0s AutomataMinimizationTime, 3 MinimizatonAttempts, 0 StatesRemovedByMinimization, 0 NontrivialMinimizations, HoareAnnotationStatistics: No data available, RefinementEngineStatistics: TRACE_CHECK: 0.0s SsaConstructionTime, 0.2s SatisfiabilityAnalysisTime, 0.8s InterpolantComputationTime, 135 NumberOfCodeBlocks, 135 NumberOfCodeBlocksAsserted, 8 NumberOfCheckSat, 133 ConstructedInterpolants, 0 QuantifiedInterpolants, 5245 SizeOfPredicates, 5 NumberOfNonLiveVariables, 190 ConjunctsInSsa, 9 ConjunctsInUnsatCore, 7 InterpolantComputations, 1 PerfectInterpolantSequences, 47/57 InterpolantCoveringCapability, INVARIANT_SYNTHESIS: No data available, INTERPOLANT_CONSOLIDATION: No data available, ABSTRACT_INTERPRETATION: No data available, PDR: No data available, ACCELERATED_INTERPOLATION: No data available, SIFA: No data available, ReuseStatistics: No data available RESULT: Ultimate proved your program to be incorrect! Received shutdown request...