java -Xmx6000000000 -jar ./plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -data ./data --generate-csv --csv-dir ../../../releaseScripts/default/UAutomizer-linux/csv -tc ../../../trunk/examples/toolchains/AutomizerC.xml -s ../../../trunk/examples/settings/cade18-smtinterpol/svcomp-DerefFreeMemtrack-32bit-Automizer_Camel.epf -i ../../../trunk/examples/svcomp/list-properties/simple_built_from_end_true-unreach-call_false-valid-memtrack.i -------------------------------------------------------------------------------- This is Ultimate 0.1.23-ccafca9-m [2018-02-04 01:04:54,231 INFO L170 SettingsManager]: Resetting all preferences to default values... [2018-02-04 01:04:54,232 INFO L174 SettingsManager]: Resetting UltimateCore preferences to default values [2018-02-04 01:04:54,246 INFO L177 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2018-02-04 01:04:54,246 INFO L174 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2018-02-04 01:04:54,247 INFO L174 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2018-02-04 01:04:54,247 INFO L174 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2018-02-04 01:04:54,248 INFO L174 SettingsManager]: Resetting LassoRanker preferences to default values [2018-02-04 01:04:54,250 INFO L174 SettingsManager]: Resetting Reaching Definitions preferences to default values [2018-02-04 01:04:54,251 INFO L174 SettingsManager]: Resetting SyntaxChecker preferences to default values [2018-02-04 01:04:54,251 INFO L177 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2018-02-04 01:04:54,252 INFO L174 SettingsManager]: Resetting LTL2Aut preferences to default values [2018-02-04 01:04:54,252 INFO L174 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2018-02-04 01:04:54,253 INFO L174 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2018-02-04 01:04:54,254 INFO L174 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2018-02-04 01:04:54,256 INFO L174 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2018-02-04 01:04:54,257 INFO L174 SettingsManager]: Resetting CodeCheck preferences to default values [2018-02-04 01:04:54,259 INFO L174 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2018-02-04 01:04:54,259 INFO L174 SettingsManager]: Resetting RCFGBuilder preferences to default values [2018-02-04 01:04:54,260 INFO L174 SettingsManager]: Resetting TraceAbstraction preferences to default values [2018-02-04 01:04:54,262 INFO L177 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... [2018-02-04 01:04:54,262 INFO L177 SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring... [2018-02-04 01:04:54,262 INFO L174 SettingsManager]: Resetting IcfgTransformer preferences to default values [2018-02-04 01:04:54,263 INFO L174 SettingsManager]: Resetting Boogie Printer preferences to default values [2018-02-04 01:04:54,264 INFO L174 SettingsManager]: Resetting Witness Printer preferences to default values [2018-02-04 01:04:54,265 INFO L177 SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring... [2018-02-04 01:04:54,265 INFO L174 SettingsManager]: Resetting CDTParser preferences to default values [2018-02-04 01:04:54,265 INFO L177 SettingsManager]: PEA to Boogie provides no preferences, ignoring... [2018-02-04 01:04:54,266 INFO L177 SettingsManager]: AutomataScriptParser provides no preferences, ignoring... [2018-02-04 01:04:54,266 INFO L174 SettingsManager]: Resetting Witness Parser preferences to default values [2018-02-04 01:04:54,266 INFO L181 SettingsManager]: Finished resetting all preferences to default values... [2018-02-04 01:04:54,266 INFO L98 SettingsManager]: Beginning loading settings from /home/ultimate/work/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/settings/cade18-smtinterpol/svcomp-DerefFreeMemtrack-32bit-Automizer_Camel.epf [2018-02-04 01:04:54,276 INFO L110 SettingsManager]: Loading preferences was successful [2018-02-04 01:04:54,276 INFO L112 SettingsManager]: Preferences different from defaults after loading the file: [2018-02-04 01:04:54,277 INFO L131 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2018-02-04 01:04:54,277 INFO L133 SettingsManager]: * Create parallel compositions if possible=false [2018-02-04 01:04:54,277 INFO L133 SettingsManager]: * Use SBE=true [2018-02-04 01:04:54,278 INFO L131 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2018-02-04 01:04:54,278 INFO L133 SettingsManager]: * sizeof long=4 [2018-02-04 01:04:54,278 INFO L133 SettingsManager]: * Check unreachability of error function in SV-COMP mode=false [2018-02-04 01:04:54,278 INFO L133 SettingsManager]: * Overapproximate operations on floating types=true [2018-02-04 01:04:54,278 INFO L133 SettingsManager]: * sizeof POINTER=4 [2018-02-04 01:04:54,278 INFO L133 SettingsManager]: * Check division by zero=IGNORE [2018-02-04 01:04:54,279 INFO L133 SettingsManager]: * Check for the main procedure if all allocated memory was freed=true [2018-02-04 01:04:54,279 INFO L133 SettingsManager]: * Bitprecise bitfields=true [2018-02-04 01:04:54,279 INFO L133 SettingsManager]: * SV-COMP memtrack compatibility mode=true [2018-02-04 01:04:54,279 INFO L133 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2018-02-04 01:04:54,279 INFO L133 SettingsManager]: * sizeof long double=12 [2018-02-04 01:04:54,279 INFO L131 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2018-02-04 01:04:54,279 INFO L133 SettingsManager]: * Size of a code block=SequenceOfStatements [2018-02-04 01:04:54,280 INFO L133 SettingsManager]: * To the following directory=./dump/ [2018-02-04 01:04:54,280 INFO L133 SettingsManager]: * SMT solver=External_DefaultMode [2018-02-04 01:04:54,280 INFO L133 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2018-02-04 01:04:54,280 INFO L131 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2018-02-04 01:04:54,280 INFO L133 SettingsManager]: * Interpolant automaton=TWOTRACK [2018-02-04 01:04:54,280 INFO L133 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2018-02-04 01:04:54,280 INFO L133 SettingsManager]: * Trace refinement strategy=CAMEL [2018-02-04 01:04:54,310 INFO L81 nceAwareModelManager]: Repository-Root is: /tmp [2018-02-04 01:04:54,322 INFO L266 ainManager$Toolchain]: [Toolchain 1]: Parser(s) successfully initialized [2018-02-04 01:04:54,325 INFO L222 ainManager$Toolchain]: [Toolchain 1]: Toolchain data selected. [2018-02-04 01:04:54,326 INFO L271 PluginConnector]: Initializing CDTParser... [2018-02-04 01:04:54,326 INFO L276 PluginConnector]: CDTParser initialized [2018-02-04 01:04:54,327 INFO L431 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /home/ultimate/work/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/list-properties/simple_built_from_end_true-unreach-call_false-valid-memtrack.i [2018-02-04 01:04:54,447 INFO L304 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2018-02-04 01:04:54,448 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2018-02-04 01:04:54,449 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2018-02-04 01:04:54,449 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2018-02-04 01:04:54,453 INFO L276 PluginConnector]: CACSL2BoogieTranslator initialized [2018-02-04 01:04:54,454 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,456 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@4d3ffa22 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54, skipping insertion in model container [2018-02-04 01:04:54,456 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,470 INFO L153 Dispatcher]: Using SV-COMP mode [2018-02-04 01:04:54,497 INFO L153 Dispatcher]: Using SV-COMP mode [2018-02-04 01:04:54,579 INFO L450 PostProcessor]: Settings: Checked method=main [2018-02-04 01:04:54,590 INFO L450 PostProcessor]: Settings: Checked method=main [2018-02-04 01:04:54,593 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54 WrapperNode [2018-02-04 01:04:54,594 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2018-02-04 01:04:54,594 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2018-02-04 01:04:54,594 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2018-02-04 01:04:54,594 INFO L276 PluginConnector]: Boogie Preprocessor initialized [2018-02-04 01:04:54,603 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,603 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,611 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,611 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,614 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,617 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,618 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (1/1) ... [2018-02-04 01:04:54,619 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2018-02-04 01:04:54,619 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2018-02-04 01:04:54,619 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2018-02-04 01:04:54,619 INFO L276 PluginConnector]: RCFGBuilder initialized [2018-02-04 01:04:54,620 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (1/1) ... No working directory specified, using /home/ultimate/work/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 [2018-02-04 01:04:54,652 INFO L136 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2018-02-04 01:04:54,652 INFO L136 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2018-02-04 01:04:54,652 INFO L136 BoogieDeclarations]: Found implementation of procedure exit [2018-02-04 01:04:54,652 INFO L136 BoogieDeclarations]: Found implementation of procedure main [2018-02-04 01:04:54,652 INFO L128 BoogieDeclarations]: Found specification of procedure write~$Pointer$ [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure read~$Pointer$ [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure write~int [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure read~int [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure ULTIMATE.free [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure ULTIMATE.dealloc [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure #Ultimate.alloc [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure __VERIFIER_error [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_int [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure malloc [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure exit [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure main [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2018-02-04 01:04:54,653 INFO L128 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2018-02-04 01:04:54,785 INFO L257 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2018-02-04 01:04:54,785 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 04.02 01:04:54 BoogieIcfgContainer [2018-02-04 01:04:54,785 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2018-02-04 01:04:54,786 INFO L113 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2018-02-04 01:04:54,786 INFO L271 PluginConnector]: Initializing TraceAbstraction... [2018-02-04 01:04:54,788 INFO L276 PluginConnector]: TraceAbstraction initialized [2018-02-04 01:04:54,788 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 04.02 01:04:54" (1/3) ... [2018-02-04 01:04:54,788 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@3c096ed4 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 04.02 01:04:54, skipping insertion in model container [2018-02-04 01:04:54,788 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 04.02 01:04:54" (2/3) ... [2018-02-04 01:04:54,789 INFO L205 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@3c096ed4 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 04.02 01:04:54, skipping insertion in model container [2018-02-04 01:04:54,789 INFO L185 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 04.02 01:04:54" (3/3) ... [2018-02-04 01:04:54,790 INFO L107 eAbstractionObserver]: Analyzing ICFG simple_built_from_end_true-unreach-call_false-valid-memtrack.i [2018-02-04 01:04:54,795 INFO L128 ceAbstractionStarter]: Automizer settings: Hoare:false NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2018-02-04 01:04:54,800 INFO L140 ceAbstractionStarter]: Appying trace abstraction to program that has 9 error locations. [2018-02-04 01:04:54,829 INFO L322 AbstractCegarLoop]: Interprodecural is true [2018-02-04 01:04:54,829 INFO L323 AbstractCegarLoop]: Hoare is false [2018-02-04 01:04:54,829 INFO L324 AbstractCegarLoop]: Compute interpolants for FPandBP [2018-02-04 01:04:54,829 INFO L325 AbstractCegarLoop]: Backedges is TWOTRACK [2018-02-04 01:04:54,829 INFO L326 AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION [2018-02-04 01:04:54,830 INFO L327 AbstractCegarLoop]: Difference is false [2018-02-04 01:04:54,830 INFO L328 AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA [2018-02-04 01:04:54,830 INFO L333 AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce======== [2018-02-04 01:04:54,830 INFO L87 2NestedWordAutomaton]: Mode: main mode - execution starts in main procedure [2018-02-04 01:04:54,838 INFO L276 IsEmpty]: Start isEmpty. Operand 38 states. [2018-02-04 01:04:54,845 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 10 [2018-02-04 01:04:54,845 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:54,846 INFO L351 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:54,847 INFO L371 AbstractCegarLoop]: === Iteration 1 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:54,850 INFO L82 PathProgramCache]: Analyzing trace with hash -119107064, now seen corresponding path program 1 times [2018-02-04 01:04:54,851 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:54,852 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:54,883 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:54,883 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:54,883 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:54,908 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-02-04 01:04:54,914 WARN L137 erpolLogProxyWrapper]: Using partial proofs (cut at CNF-level). Set option :produce-proofs to true to get complete proofs. [2018-02-04 01:04:54,937 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-02-04 01:04:54,939 INFO L320 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-02-04 01:04:54,940 INFO L335 seRefinementStrategy]: Number of different interpolants: perfect sequences [2] imperfect sequences [] total 2 [2018-02-04 01:04:54,941 INFO L409 AbstractCegarLoop]: Interpolant automaton has 2 states [2018-02-04 01:04:54,949 INFO L132 InterpolantAutomaton]: Constructing interpolant automaton starting with 2 interpolants. [2018-02-04 01:04:54,949 INFO L133 InterpolantAutomaton]: CoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2018-02-04 01:04:54,951 INFO L87 Difference]: Start difference. First operand 38 states. Second operand 2 states. [2018-02-04 01:04:54,962 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-02-04 01:04:54,962 INFO L93 Difference]: Finished difference Result 38 states and 39 transitions. [2018-02-04 01:04:54,962 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 2 states. [2018-02-04 01:04:54,963 INFO L78 Accepts]: Start accepts. Automaton has 2 states. Word has length 9 [2018-02-04 01:04:54,963 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-02-04 01:04:54,969 INFO L225 Difference]: With dead ends: 38 [2018-02-04 01:04:54,969 INFO L226 Difference]: Without dead ends: 31 [2018-02-04 01:04:54,970 INFO L554 BasicCegarLoop]: 0 DeclaredPredicates, 2 GetRequests, 2 SyntacticMatches, 0 SemanticMatches, 0 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2018-02-04 01:04:55,034 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 31 states. [2018-02-04 01:04:55,043 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 31 to 31. [2018-02-04 01:04:55,044 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 31 states. [2018-02-04 01:04:55,044 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 31 states to 31 states and 32 transitions. [2018-02-04 01:04:55,045 INFO L78 Accepts]: Start accepts. Automaton has 31 states and 32 transitions. Word has length 9 [2018-02-04 01:04:55,045 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-02-04 01:04:55,046 INFO L432 AbstractCegarLoop]: Abstraction has 31 states and 32 transitions. [2018-02-04 01:04:55,046 INFO L433 AbstractCegarLoop]: Interpolant automaton has 2 states. [2018-02-04 01:04:55,046 INFO L276 IsEmpty]: Start isEmpty. Operand 31 states and 32 transitions. [2018-02-04 01:04:55,046 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 13 [2018-02-04 01:04:55,046 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:55,046 INFO L351 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:55,046 INFO L371 AbstractCegarLoop]: === Iteration 2 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:55,046 INFO L82 PathProgramCache]: Analyzing trace with hash -1438918584, now seen corresponding path program 1 times [2018-02-04 01:04:55,047 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:55,047 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:55,047 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,047 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:55,047 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,056 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-02-04 01:04:55,057 WARN L137 erpolLogProxyWrapper]: Using partial proofs (cut at CNF-level). Set option :produce-proofs to true to get complete proofs. [2018-02-04 01:04:55,080 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-02-04 01:04:55,080 INFO L320 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-02-04 01:04:55,081 INFO L335 seRefinementStrategy]: Number of different interpolants: perfect sequences [2] imperfect sequences [] total 2 [2018-02-04 01:04:55,081 INFO L409 AbstractCegarLoop]: Interpolant automaton has 3 states [2018-02-04 01:04:55,082 INFO L132 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2018-02-04 01:04:55,082 INFO L133 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2018-02-04 01:04:55,082 INFO L87 Difference]: Start difference. First operand 31 states and 32 transitions. Second operand 3 states. [2018-02-04 01:04:55,126 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-02-04 01:04:55,126 INFO L93 Difference]: Finished difference Result 46 states and 48 transitions. [2018-02-04 01:04:55,126 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2018-02-04 01:04:55,126 INFO L78 Accepts]: Start accepts. Automaton has 3 states. Word has length 12 [2018-02-04 01:04:55,127 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-02-04 01:04:55,127 INFO L225 Difference]: With dead ends: 46 [2018-02-04 01:04:55,127 INFO L226 Difference]: Without dead ends: 45 [2018-02-04 01:04:55,128 INFO L554 BasicCegarLoop]: 0 DeclaredPredicates, 2 GetRequests, 1 SyntacticMatches, 0 SemanticMatches, 1 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2018-02-04 01:04:55,128 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 45 states. [2018-02-04 01:04:55,131 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 45 to 40. [2018-02-04 01:04:55,131 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 40 states. [2018-02-04 01:04:55,131 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 40 states to 40 states and 46 transitions. [2018-02-04 01:04:55,131 INFO L78 Accepts]: Start accepts. Automaton has 40 states and 46 transitions. Word has length 12 [2018-02-04 01:04:55,132 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-02-04 01:04:55,132 INFO L432 AbstractCegarLoop]: Abstraction has 40 states and 46 transitions. [2018-02-04 01:04:55,132 INFO L433 AbstractCegarLoop]: Interpolant automaton has 3 states. [2018-02-04 01:04:55,132 INFO L276 IsEmpty]: Start isEmpty. Operand 40 states and 46 transitions. [2018-02-04 01:04:55,132 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 13 [2018-02-04 01:04:55,132 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:55,132 INFO L351 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:55,132 INFO L371 AbstractCegarLoop]: === Iteration 3 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:55,132 INFO L82 PathProgramCache]: Analyzing trace with hash -1438918540, now seen corresponding path program 1 times [2018-02-04 01:04:55,133 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:55,133 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:55,133 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,133 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:55,133 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,139 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-02-04 01:04:55,140 WARN L137 erpolLogProxyWrapper]: Using partial proofs (cut at CNF-level). Set option :produce-proofs to true to get complete proofs. [2018-02-04 01:04:55,162 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-02-04 01:04:55,163 INFO L320 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-02-04 01:04:55,163 INFO L335 seRefinementStrategy]: Number of different interpolants: perfect sequences [3] imperfect sequences [] total 3 [2018-02-04 01:04:55,163 INFO L409 AbstractCegarLoop]: Interpolant automaton has 3 states [2018-02-04 01:04:55,163 INFO L132 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2018-02-04 01:04:55,163 INFO L133 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2018-02-04 01:04:55,164 INFO L87 Difference]: Start difference. First operand 40 states and 46 transitions. Second operand 3 states. [2018-02-04 01:04:55,180 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-02-04 01:04:55,180 INFO L93 Difference]: Finished difference Result 46 states and 47 transitions. [2018-02-04 01:04:55,180 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2018-02-04 01:04:55,180 INFO L78 Accepts]: Start accepts. Automaton has 3 states. Word has length 12 [2018-02-04 01:04:55,181 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-02-04 01:04:55,181 INFO L225 Difference]: With dead ends: 46 [2018-02-04 01:04:55,181 INFO L226 Difference]: Without dead ends: 44 [2018-02-04 01:04:55,181 INFO L554 BasicCegarLoop]: 0 DeclaredPredicates, 3 GetRequests, 2 SyntacticMatches, 0 SemanticMatches, 1 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2018-02-04 01:04:55,181 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 44 states. [2018-02-04 01:04:55,183 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 44 to 34. [2018-02-04 01:04:55,183 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 34 states. [2018-02-04 01:04:55,183 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 34 states to 34 states and 35 transitions. [2018-02-04 01:04:55,183 INFO L78 Accepts]: Start accepts. Automaton has 34 states and 35 transitions. Word has length 12 [2018-02-04 01:04:55,183 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-02-04 01:04:55,184 INFO L432 AbstractCegarLoop]: Abstraction has 34 states and 35 transitions. [2018-02-04 01:04:55,184 INFO L433 AbstractCegarLoop]: Interpolant automaton has 3 states. [2018-02-04 01:04:55,184 INFO L276 IsEmpty]: Start isEmpty. Operand 34 states and 35 transitions. [2018-02-04 01:04:55,184 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 14 [2018-02-04 01:04:55,184 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:55,185 INFO L351 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:55,185 INFO L371 AbstractCegarLoop]: === Iteration 4 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:55,186 INFO L82 PathProgramCache]: Analyzing trace with hash -1655605995, now seen corresponding path program 1 times [2018-02-04 01:04:55,186 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:55,186 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:55,186 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,186 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:55,186 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,199 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-02-04 01:04:55,200 WARN L137 erpolLogProxyWrapper]: Using partial proofs (cut at CNF-level). Set option :produce-proofs to true to get complete proofs. [2018-02-04 01:04:55,227 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-02-04 01:04:55,227 INFO L320 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-02-04 01:04:55,227 INFO L335 seRefinementStrategy]: Number of different interpolants: perfect sequences [3] imperfect sequences [] total 3 [2018-02-04 01:04:55,228 INFO L409 AbstractCegarLoop]: Interpolant automaton has 4 states [2018-02-04 01:04:55,228 INFO L132 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2018-02-04 01:04:55,228 INFO L133 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2018-02-04 01:04:55,228 INFO L87 Difference]: Start difference. First operand 34 states and 35 transitions. Second operand 4 states. [2018-02-04 01:04:55,263 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-02-04 01:04:55,263 INFO L93 Difference]: Finished difference Result 34 states and 35 transitions. [2018-02-04 01:04:55,264 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2018-02-04 01:04:55,264 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 13 [2018-02-04 01:04:55,264 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-02-04 01:04:55,264 INFO L225 Difference]: With dead ends: 34 [2018-02-04 01:04:55,264 INFO L226 Difference]: Without dead ends: 34 [2018-02-04 01:04:55,264 INFO L554 BasicCegarLoop]: 0 DeclaredPredicates, 5 GetRequests, 2 SyntacticMatches, 0 SemanticMatches, 3 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=9, Invalid=11, Unknown=0, NotChecked=0, Total=20 [2018-02-04 01:04:55,265 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 34 states. [2018-02-04 01:04:55,266 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 34 to 32. [2018-02-04 01:04:55,266 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 32 states. [2018-02-04 01:04:55,266 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 32 states to 32 states and 33 transitions. [2018-02-04 01:04:55,266 INFO L78 Accepts]: Start accepts. Automaton has 32 states and 33 transitions. Word has length 13 [2018-02-04 01:04:55,267 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-02-04 01:04:55,267 INFO L432 AbstractCegarLoop]: Abstraction has 32 states and 33 transitions. [2018-02-04 01:04:55,267 INFO L433 AbstractCegarLoop]: Interpolant automaton has 4 states. [2018-02-04 01:04:55,267 INFO L276 IsEmpty]: Start isEmpty. Operand 32 states and 33 transitions. [2018-02-04 01:04:55,267 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 14 [2018-02-04 01:04:55,267 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:55,267 INFO L351 BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:55,267 INFO L371 AbstractCegarLoop]: === Iteration 5 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:55,267 INFO L82 PathProgramCache]: Analyzing trace with hash -1655605994, now seen corresponding path program 1 times [2018-02-04 01:04:55,267 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:55,267 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:55,268 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,268 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:55,268 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,278 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-02-04 01:04:55,279 WARN L137 erpolLogProxyWrapper]: Using partial proofs (cut at CNF-level). Set option :produce-proofs to true to get complete proofs. [2018-02-04 01:04:55,346 INFO L134 CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-02-04 01:04:55,347 INFO L320 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-02-04 01:04:55,347 INFO L335 seRefinementStrategy]: Number of different interpolants: perfect sequences [3] imperfect sequences [] total 3 [2018-02-04 01:04:55,347 INFO L409 AbstractCegarLoop]: Interpolant automaton has 4 states [2018-02-04 01:04:55,347 INFO L132 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2018-02-04 01:04:55,347 INFO L133 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2018-02-04 01:04:55,348 INFO L87 Difference]: Start difference. First operand 32 states and 33 transitions. Second operand 4 states. [2018-02-04 01:04:55,384 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-02-04 01:04:55,384 INFO L93 Difference]: Finished difference Result 32 states and 33 transitions. [2018-02-04 01:04:55,384 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2018-02-04 01:04:55,384 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 13 [2018-02-04 01:04:55,384 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-02-04 01:04:55,385 INFO L225 Difference]: With dead ends: 32 [2018-02-04 01:04:55,385 INFO L226 Difference]: Without dead ends: 32 [2018-02-04 01:04:55,385 INFO L554 BasicCegarLoop]: 0 DeclaredPredicates, 6 GetRequests, 2 SyntacticMatches, 1 SemanticMatches, 3 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=9, Invalid=11, Unknown=0, NotChecked=0, Total=20 [2018-02-04 01:04:55,385 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 32 states. [2018-02-04 01:04:55,387 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 32 to 30. [2018-02-04 01:04:55,387 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 30 states. [2018-02-04 01:04:55,388 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 30 states to 30 states and 31 transitions. [2018-02-04 01:04:55,388 INFO L78 Accepts]: Start accepts. Automaton has 30 states and 31 transitions. Word has length 13 [2018-02-04 01:04:55,388 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-02-04 01:04:55,388 INFO L432 AbstractCegarLoop]: Abstraction has 30 states and 31 transitions. [2018-02-04 01:04:55,388 INFO L433 AbstractCegarLoop]: Interpolant automaton has 4 states. [2018-02-04 01:04:55,388 INFO L276 IsEmpty]: Start isEmpty. Operand 30 states and 31 transitions. [2018-02-04 01:04:55,389 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 22 [2018-02-04 01:04:55,389 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:55,389 INFO L351 BasicCegarLoop]: trace histogram [2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:55,389 INFO L371 AbstractCegarLoop]: === Iteration 6 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:55,390 INFO L82 PathProgramCache]: Analyzing trace with hash -252306105, now seen corresponding path program 1 times [2018-02-04 01:04:55,390 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:55,390 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:55,391 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,391 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:55,391 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,402 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-02-04 01:04:55,402 WARN L137 erpolLogProxyWrapper]: Using partial proofs (cut at CNF-level). Set option :produce-proofs to true to get complete proofs. [2018-02-04 01:04:55,433 INFO L134 CoverageAnalysis]: Checked inductivity of 3 backedges. 3 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-02-04 01:04:55,433 INFO L320 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-02-04 01:04:55,433 INFO L335 seRefinementStrategy]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5 [2018-02-04 01:04:55,433 INFO L409 AbstractCegarLoop]: Interpolant automaton has 5 states [2018-02-04 01:04:55,433 INFO L132 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2018-02-04 01:04:55,433 INFO L133 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2018-02-04 01:04:55,433 INFO L87 Difference]: Start difference. First operand 30 states and 31 transitions. Second operand 5 states. [2018-02-04 01:04:55,472 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-02-04 01:04:55,473 INFO L93 Difference]: Finished difference Result 46 states and 47 transitions. [2018-02-04 01:04:55,473 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2018-02-04 01:04:55,473 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 21 [2018-02-04 01:04:55,473 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-02-04 01:04:55,474 INFO L225 Difference]: With dead ends: 46 [2018-02-04 01:04:55,474 INFO L226 Difference]: Without dead ends: 46 [2018-02-04 01:04:55,474 INFO L554 BasicCegarLoop]: 0 DeclaredPredicates, 8 GetRequests, 3 SyntacticMatches, 0 SemanticMatches, 5 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=17, Invalid=25, Unknown=0, NotChecked=0, Total=42 [2018-02-04 01:04:55,474 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 46 states. [2018-02-04 01:04:55,475 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 46 to 32. [2018-02-04 01:04:55,475 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 32 states. [2018-02-04 01:04:55,476 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 32 states to 32 states and 33 transitions. [2018-02-04 01:04:55,476 INFO L78 Accepts]: Start accepts. Automaton has 32 states and 33 transitions. Word has length 21 [2018-02-04 01:04:55,476 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-02-04 01:04:55,476 INFO L432 AbstractCegarLoop]: Abstraction has 32 states and 33 transitions. [2018-02-04 01:04:55,476 INFO L433 AbstractCegarLoop]: Interpolant automaton has 5 states. [2018-02-04 01:04:55,476 INFO L276 IsEmpty]: Start isEmpty. Operand 32 states and 33 transitions. [2018-02-04 01:04:55,477 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 22 [2018-02-04 01:04:55,477 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:55,477 INFO L351 BasicCegarLoop]: trace histogram [2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:55,477 INFO L371 AbstractCegarLoop]: === Iteration 7 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:55,477 INFO L82 PathProgramCache]: Analyzing trace with hash -252306061, now seen corresponding path program 1 times [2018-02-04 01:04:55,477 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:55,477 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:55,478 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,478 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:55,478 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,484 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-02-04 01:04:55,485 WARN L137 erpolLogProxyWrapper]: Using partial proofs (cut at CNF-level). Set option :produce-proofs to true to get complete proofs. [2018-02-04 01:04:55,505 INFO L134 CoverageAnalysis]: Checked inductivity of 3 backedges. 3 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-02-04 01:04:55,506 INFO L320 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-02-04 01:04:55,506 INFO L335 seRefinementStrategy]: Number of different interpolants: perfect sequences [3] imperfect sequences [] total 3 [2018-02-04 01:04:55,506 INFO L409 AbstractCegarLoop]: Interpolant automaton has 4 states [2018-02-04 01:04:55,506 INFO L132 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2018-02-04 01:04:55,506 INFO L133 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2018-02-04 01:04:55,506 INFO L87 Difference]: Start difference. First operand 32 states and 33 transitions. Second operand 4 states. [2018-02-04 01:04:55,561 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-02-04 01:04:55,561 INFO L93 Difference]: Finished difference Result 39 states and 40 transitions. [2018-02-04 01:04:55,561 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2018-02-04 01:04:55,561 INFO L78 Accepts]: Start accepts. Automaton has 4 states. Word has length 21 [2018-02-04 01:04:55,561 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-02-04 01:04:55,562 INFO L225 Difference]: With dead ends: 39 [2018-02-04 01:04:55,562 INFO L226 Difference]: Without dead ends: 39 [2018-02-04 01:04:55,562 INFO L554 BasicCegarLoop]: 0 DeclaredPredicates, 5 GetRequests, 2 SyntacticMatches, 0 SemanticMatches, 3 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=9, Invalid=11, Unknown=0, NotChecked=0, Total=20 [2018-02-04 01:04:55,562 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 39 states. [2018-02-04 01:04:55,563 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 39 to 32. [2018-02-04 01:04:55,563 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 32 states. [2018-02-04 01:04:55,564 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 32 states to 32 states and 34 transitions. [2018-02-04 01:04:55,564 INFO L78 Accepts]: Start accepts. Automaton has 32 states and 34 transitions. Word has length 21 [2018-02-04 01:04:55,564 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-02-04 01:04:55,564 INFO L432 AbstractCegarLoop]: Abstraction has 32 states and 34 transitions. [2018-02-04 01:04:55,564 INFO L433 AbstractCegarLoop]: Interpolant automaton has 4 states. [2018-02-04 01:04:55,564 INFO L276 IsEmpty]: Start isEmpty. Operand 32 states and 34 transitions. [2018-02-04 01:04:55,564 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 22 [2018-02-04 01:04:55,564 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:55,565 INFO L351 BasicCegarLoop]: trace histogram [2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:55,565 INFO L371 AbstractCegarLoop]: === Iteration 8 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:55,565 INFO L82 PathProgramCache]: Analyzing trace with hash -252306060, now seen corresponding path program 1 times [2018-02-04 01:04:55,565 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:55,565 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:55,565 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,566 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:55,566 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,575 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2018-02-04 01:04:55,576 WARN L137 erpolLogProxyWrapper]: Using partial proofs (cut at CNF-level). Set option :produce-proofs to true to get complete proofs. [2018-02-04 01:04:55,644 INFO L134 CoverageAnalysis]: Checked inductivity of 3 backedges. 3 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked. [2018-02-04 01:04:55,644 INFO L320 seRefinementStrategy]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences. [2018-02-04 01:04:55,645 INFO L335 seRefinementStrategy]: Number of different interpolants: perfect sequences [4] imperfect sequences [] total 4 [2018-02-04 01:04:55,645 INFO L409 AbstractCegarLoop]: Interpolant automaton has 5 states [2018-02-04 01:04:55,645 INFO L132 InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants. [2018-02-04 01:04:55,645 INFO L133 InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20 [2018-02-04 01:04:55,645 INFO L87 Difference]: Start difference. First operand 32 states and 34 transitions. Second operand 5 states. [2018-02-04 01:04:55,688 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2018-02-04 01:04:55,688 INFO L93 Difference]: Finished difference Result 41 states and 42 transitions. [2018-02-04 01:04:55,688 INFO L142 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. [2018-02-04 01:04:55,688 INFO L78 Accepts]: Start accepts. Automaton has 5 states. Word has length 21 [2018-02-04 01:04:55,688 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2018-02-04 01:04:55,689 INFO L225 Difference]: With dead ends: 41 [2018-02-04 01:04:55,689 INFO L226 Difference]: Without dead ends: 41 [2018-02-04 01:04:55,689 INFO L554 BasicCegarLoop]: 0 DeclaredPredicates, 8 GetRequests, 2 SyntacticMatches, 1 SemanticMatches, 5 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=17, Invalid=25, Unknown=0, NotChecked=0, Total=42 [2018-02-04 01:04:55,689 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 41 states. [2018-02-04 01:04:55,693 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 41 to 34. [2018-02-04 01:04:55,693 INFO L82 GeneralOperation]: Start removeUnreachable. Operand 34 states. [2018-02-04 01:04:55,693 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 34 states to 34 states and 35 transitions. [2018-02-04 01:04:55,693 INFO L78 Accepts]: Start accepts. Automaton has 34 states and 35 transitions. Word has length 21 [2018-02-04 01:04:55,694 INFO L84 Accepts]: Finished accepts. word is rejected. [2018-02-04 01:04:55,694 INFO L432 AbstractCegarLoop]: Abstraction has 34 states and 35 transitions. [2018-02-04 01:04:55,694 INFO L433 AbstractCegarLoop]: Interpolant automaton has 5 states. [2018-02-04 01:04:55,694 INFO L276 IsEmpty]: Start isEmpty. Operand 34 states and 35 transitions. [2018-02-04 01:04:55,694 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 28 [2018-02-04 01:04:55,694 INFO L343 BasicCegarLoop]: Found error trace [2018-02-04 01:04:55,694 INFO L351 BasicCegarLoop]: trace histogram [2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2018-02-04 01:04:55,694 INFO L371 AbstractCegarLoop]: === Iteration 9 === [mainErr5RequiresViolation, mainErr3RequiresViolation, mainErr1RequiresViolation, mainErr7RequiresViolation, mainErr2RequiresViolation, mainErr4RequiresViolation, mainErr6RequiresViolation, mainErr0RequiresViolation, mainErr8EnsuresViolation]=== [2018-02-04 01:04:55,694 INFO L82 PathProgramCache]: Analyzing trace with hash -633867851, now seen corresponding path program 1 times [2018-02-04 01:04:55,694 INFO L213 onRefinementStrategy]: Switched to mode SMTINTERPOL_TREE_INTERPOLANTS [2018-02-04 01:04:55,695 INFO L67 tionRefinementEngine]: Using refinement strategy CamelRefinementStrategy [2018-02-04 01:04:55,695 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,695 INFO L109 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2018-02-04 01:04:55,695 INFO L125 rtionOrderModulation]: Craig nested/tree interpolation forces the following order [2018-02-04 01:04:55,702 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is sat [2018-02-04 01:04:55,713 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is sat [2018-02-04 01:04:55,729 INFO L410 BasicCegarLoop]: Counterexample might be feasible [2018-02-04 01:04:55,740 WARN L343 cessorBacktranslator]: Generated EnsuresSpecification ensures #valid == old(#valid); is not ensure(true) [2018-02-04 01:04:55,752 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction CFG 04.02 01:04:55 BoogieIcfgContainer [2018-02-04 01:04:55,752 INFO L132 PluginConnector]: ------------------------ END TraceAbstraction---------------------------- [2018-02-04 01:04:55,753 INFO L168 Benchmark]: Toolchain (without parser) took 1305.21 ms. Allocated memory was 405.8 MB in the beginning and 618.7 MB in the end (delta: 212.9 MB). Free memory was 364.0 MB in the beginning and 487.5 MB in the end (delta: -123.5 MB). Peak memory consumption was 89.4 MB. Max. memory is 5.3 GB. [2018-02-04 01:04:55,753 INFO L168 Benchmark]: CDTParser took 0.15 ms. Allocated memory is still 405.8 MB. Free memory is still 369.3 MB. There was no memory consumed. Max. memory is 5.3 GB. [2018-02-04 01:04:55,754 INFO L168 Benchmark]: CACSL2BoogieTranslator took 145.26 ms. Allocated memory is still 405.8 MB. Free memory was 362.7 MB in the beginning and 351.9 MB in the end (delta: 10.7 MB). Peak memory consumption was 10.7 MB. Max. memory is 5.3 GB. [2018-02-04 01:04:55,754 INFO L168 Benchmark]: Boogie Preprocessor took 24.92 ms. Allocated memory is still 405.8 MB. Free memory was 351.9 MB in the beginning and 350.6 MB in the end (delta: 1.3 MB). Peak memory consumption was 1.3 MB. Max. memory is 5.3 GB. [2018-02-04 01:04:55,754 INFO L168 Benchmark]: RCFGBuilder took 166.22 ms. Allocated memory is still 405.8 MB. Free memory was 350.6 MB in the beginning and 333.9 MB in the end (delta: 16.7 MB). Peak memory consumption was 16.7 MB. Max. memory is 5.3 GB. [2018-02-04 01:04:55,754 INFO L168 Benchmark]: TraceAbstraction took 966.53 ms. Allocated memory was 405.8 MB in the beginning and 618.7 MB in the end (delta: 212.9 MB). Free memory was 333.9 MB in the beginning and 487.5 MB in the end (delta: -153.5 MB). Peak memory consumption was 59.3 MB. Max. memory is 5.3 GB. [2018-02-04 01:04:55,755 INFO L344 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * CDTParser took 0.15 ms. Allocated memory is still 405.8 MB. Free memory is still 369.3 MB. There was no memory consumed. Max. memory is 5.3 GB. * CACSL2BoogieTranslator took 145.26 ms. Allocated memory is still 405.8 MB. Free memory was 362.7 MB in the beginning and 351.9 MB in the end (delta: 10.7 MB). Peak memory consumption was 10.7 MB. Max. memory is 5.3 GB. * Boogie Preprocessor took 24.92 ms. Allocated memory is still 405.8 MB. Free memory was 351.9 MB in the beginning and 350.6 MB in the end (delta: 1.3 MB). Peak memory consumption was 1.3 MB. Max. memory is 5.3 GB. * RCFGBuilder took 166.22 ms. Allocated memory is still 405.8 MB. Free memory was 350.6 MB in the beginning and 333.9 MB in the end (delta: 16.7 MB). Peak memory consumption was 16.7 MB. Max. memory is 5.3 GB. * TraceAbstraction took 966.53 ms. Allocated memory was 405.8 MB in the beginning and 618.7 MB in the end (delta: 212.9 MB). Free memory was 333.9 MB in the beginning and 487.5 MB in the end (delta: -153.5 MB). Peak memory consumption was 59.3 MB. Max. memory is 5.3 GB. * Results from de.uni_freiburg.informatik.ultimate.boogie.preprocessor: - GenericResult: Unfinished Backtranslation Generated EnsuresSpecification ensures #valid == old(#valid); is not ensure(true) * Results from de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: - UnprovableResult [Line: 626]: Unable to prove that all allocated memory was freed Unable to prove that all allocated memory was freed Reason: overapproximation of memtrack at line 626. Possible FailurePath: [L627] List t; [L628] List p = 0; VAL [p={0:0}] [L629] COND TRUE __VERIFIER_nondet_int() [L630] EXPR, FCALL malloc(sizeof(struct node)) VAL [malloc(sizeof(struct node))={13:0}, p={0:0}] [L630] t = (List) malloc(sizeof(struct node)) VAL [malloc(sizeof(struct node))={13:0}, p={0:0}, t={13:0}] [L631] COND FALSE !(t == 0) VAL [malloc(sizeof(struct node))={13:0}, p={0:0}, t={13:0}] [L632] FCALL t->h = 1 VAL [malloc(sizeof(struct node))={13:0}, p={0:0}, t={13:0}] [L633] FCALL t->n = p VAL [malloc(sizeof(struct node))={13:0}, p={0:0}, t={13:0}] [L634] p = t VAL [malloc(sizeof(struct node))={13:0}, p={13:0}, t={13:0}] [L629] COND FALSE !(__VERIFIER_nondet_int()) [L636] COND TRUE p!=0 VAL [malloc(sizeof(struct node))={13:0}, p={13:0}, t={13:0}] [L637] EXPR, FCALL p->h VAL [malloc(sizeof(struct node))={13:0}, p={13:0}, p->h=1, t={13:0}] [L637] COND FALSE !(p->h != 1) [L640] EXPR, FCALL p->n VAL [malloc(sizeof(struct node))={13:0}, p={13:0}, p->n={0:0}, t={13:0}] [L640] p = p->n [L636] COND FALSE !(p!=0) VAL [malloc(sizeof(struct node))={13:0}, p={0:0}, t={13:0}] - StatisticsResult: Ultimate Automizer benchmark data CFG has 4 procedures, 40 locations, 9 error locations. UNSAFE Result, 0.9s OverallTime, 9 OverallIterations, 2 TraceHistogramMax, 0.3s AutomataDifference, 0.0s DeadEndRemovalTime, 0.0s HoareAnnotationTime, HoareTripleCheckerStatistics: 202 SDtfs, 262 SDslu, 144 SDs, 0 SdLazy, 154 SolverSat, 15 SolverUnsat, 0 SolverUnknown, 0 SolverNotchecked, 0.1s Time, PredicateUnifierStatistics: 0 DeclaredPredicates, 39 GetRequests, 16 SyntacticMatches, 2 SemanticMatches, 21 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.1s Time, 0.0s BasicInterpolantAutomatonTime, BiggestAbstraction: size=40occurred in iteration=2, traceCheckStatistics: No data available, InterpolantConsolidationStatistics: No data available, PathInvariantsStatistics: No data available, 0/0 InterpolantCoveringCapability, TotalInterpolationStatistics: No data available, 0.0s AbstIntTime, 0 AbstIntIterations, 0 AbstIntStrong, NaN AbsIntWeakeningRatio, NaN AbsIntAvgWeakeningVarsNumRemoved, NaN AbsIntAvgWeakenedConjuncts, 0.0s DumpTime, AutomataMinimizationStatistics: 0.0s AutomataMinimizationTime, 8 MinimizatonAttempts, 47 StatesRemovedByMinimization, 7 NontrivialMinimizations, HoareAnnotationStatistics: No data available, RefinementEngineStatistics: TraceCheckStatistics: 0.0s SsaConstructionTime, 0.0s SatisfiabilityAnalysisTime, 0.2s InterpolantComputationTime, 149 NumberOfCodeBlocks, 149 NumberOfCodeBlocksAsserted, 9 NumberOfCheckSat, 114 ConstructedInterpolants, 0 QuantifiedInterpolants, 5710 SizeOfPredicates, 0 NumberOfNonLiveVariables, 0 ConjunctsInSsa, 0 ConjunctsInUnsatCore, 8 InterpolantComputations, 8 PerfectInterpolantSequences, 9/9 InterpolantCoveringCapability, InvariantSynthesisStatistics: No data available, InterpolantConsolidationStatistics: No data available, ReuseStatistics: No data available RESULT: Ultimate could not prove your program: unable to determine feasibility of some traces Written .csv to /home/ultimate/work/ultimate/releaseScripts/default/UAutomizer-linux/../../../releaseScripts/default/UAutomizer-linux/csv/simple_built_from_end_true-unreach-call_false-valid-memtrack.i_svcomp-DerefFreeMemtrack-32bit-Automizer_Camel.epf_AutomizerC.xml/Csv-Benchmark-0-2018-02-04_01-04-55-760.csv Written .csv to /home/ultimate/work/ultimate/releaseScripts/default/UAutomizer-linux/../../../releaseScripts/default/UAutomizer-linux/csv/simple_built_from_end_true-unreach-call_false-valid-memtrack.i_svcomp-DerefFreeMemtrack-32bit-Automizer_Camel.epf_AutomizerC.xml/Csv-TraceAbstractionBenchmarks-0-2018-02-04_01-04-55-760.csv Received shutdown request...