java -Xmx8000000000 -Xss4m -jar ./plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -data @noDefault -ultimatedata ./data -tc ../../../trunk/examples/toolchains/AbstractInterpretationInline.xml -s ../../../trunk/examples/settings/ai/array-bench/reach_32bit_compound_exp_cong.epf -i ../../../trunk/examples/programs/scalable/CTR_CounterExp-4bit.bpl -------------------------------------------------------------------------------- This is Ultimate 0.1.24-b8c145f [2019-08-05 12:16:28,441 INFO L177 SettingsManager]: Resetting all preferences to default values... [2019-08-05 12:16:28,446 INFO L181 SettingsManager]: Resetting UltimateCore preferences to default values [2019-08-05 12:16:28,461 INFO L184 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2019-08-05 12:16:28,462 INFO L181 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2019-08-05 12:16:28,464 INFO L181 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2019-08-05 12:16:28,466 INFO L181 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2019-08-05 12:16:28,469 INFO L181 SettingsManager]: Resetting LassoRanker preferences to default values [2019-08-05 12:16:28,471 INFO L181 SettingsManager]: Resetting Reaching Definitions preferences to default values [2019-08-05 12:16:28,473 INFO L181 SettingsManager]: Resetting SyntaxChecker preferences to default values [2019-08-05 12:16:28,474 INFO L181 SettingsManager]: Resetting Symbolic Interpretation preferences to default values [2019-08-05 12:16:28,475 INFO L184 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2019-08-05 12:16:28,475 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2019-08-05 12:16:28,478 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2019-08-05 12:16:28,479 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2019-08-05 12:16:28,481 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2019-08-05 12:16:28,482 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2019-08-05 12:16:28,483 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2019-08-05 12:16:28,486 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2019-08-05 12:16:28,496 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2019-08-05 12:16:28,501 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2019-08-05 12:16:28,502 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2019-08-05 12:16:28,505 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2019-08-05 12:16:28,506 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2019-08-05 12:16:28,510 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... [2019-08-05 12:16:28,510 INFO L184 SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring... [2019-08-05 12:16:28,510 INFO L181 SettingsManager]: Resetting TreeAutomizer preferences to default values [2019-08-05 12:16:28,511 INFO L181 SettingsManager]: Resetting IcfgToChc preferences to default values [2019-08-05 12:16:28,512 INFO L181 SettingsManager]: Resetting IcfgTransformer preferences to default values [2019-08-05 12:16:28,514 INFO L184 SettingsManager]: ReqToTest provides no preferences, ignoring... [2019-08-05 12:16:28,514 INFO L181 SettingsManager]: Resetting Boogie Printer preferences to default values [2019-08-05 12:16:28,517 INFO L181 SettingsManager]: Resetting ChcSmtPrinter preferences to default values [2019-08-05 12:16:28,518 INFO L181 SettingsManager]: Resetting ReqPrinter preferences to default values [2019-08-05 12:16:28,519 INFO L181 SettingsManager]: Resetting Witness Printer preferences to default values [2019-08-05 12:16:28,520 INFO L184 SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring... [2019-08-05 12:16:28,520 INFO L181 SettingsManager]: Resetting CDTParser preferences to default values [2019-08-05 12:16:28,522 INFO L184 SettingsManager]: AutomataScriptParser provides no preferences, ignoring... [2019-08-05 12:16:28,523 INFO L184 SettingsManager]: ReqParser provides no preferences, ignoring... [2019-08-05 12:16:28,523 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2019-08-05 12:16:28,524 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2019-08-05 12:16:28,525 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2019-08-05 12:16:28,529 INFO L101 SettingsManager]: Beginning loading settings from /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/settings/ai/array-bench/reach_32bit_compound_exp_cong.epf [2019-08-05 12:16:28,548 INFO L113 SettingsManager]: Loading preferences was successful [2019-08-05 12:16:28,548 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2019-08-05 12:16:28,549 INFO L136 SettingsManager]: Preferences of Boogie Preprocessor differ from their defaults: [2019-08-05 12:16:28,549 INFO L138 SettingsManager]: * Show backtranslation warnings=false [2019-08-05 12:16:28,550 INFO L136 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2019-08-05 12:16:28,550 INFO L138 SettingsManager]: * User list type=DISABLED [2019-08-05 12:16:28,550 INFO L138 SettingsManager]: * Inline calls to unimplemented procedures=true [2019-08-05 12:16:28,551 INFO L136 SettingsManager]: Preferences of Abstract Interpretation differ from their defaults: [2019-08-05 12:16:28,551 INFO L138 SettingsManager]: * Explicit value domain=true [2019-08-05 12:16:28,551 INFO L138 SettingsManager]: * Abstract domain for RCFG-of-the-future=PoormanAbstractDomain [2019-08-05 12:16:28,552 INFO L138 SettingsManager]: * Octagon Domain=false [2019-08-05 12:16:28,552 INFO L138 SettingsManager]: * Abstract domain=CompoundDomain [2019-08-05 12:16:28,552 INFO L138 SettingsManager]: * Check feasibility of abstract posts with an SMT solver=true [2019-08-05 12:16:28,552 INFO L138 SettingsManager]: * Interval Domain=false [2019-08-05 12:16:28,555 INFO L136 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2019-08-05 12:16:28,555 INFO L138 SettingsManager]: * Create parallel compositions if possible=false [2019-08-05 12:16:28,556 INFO L138 SettingsManager]: * Use SBE=true [2019-08-05 12:16:28,556 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2019-08-05 12:16:28,556 INFO L138 SettingsManager]: * sizeof long=4 [2019-08-05 12:16:28,556 INFO L138 SettingsManager]: * Overapproximate operations on floating types=true [2019-08-05 12:16:28,557 INFO L138 SettingsManager]: * sizeof POINTER=4 [2019-08-05 12:16:28,557 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2019-08-05 12:16:28,557 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2019-08-05 12:16:28,557 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2019-08-05 12:16:28,557 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2019-08-05 12:16:28,558 INFO L138 SettingsManager]: * sizeof long double=12 [2019-08-05 12:16:28,558 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2019-08-05 12:16:28,558 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2019-08-05 12:16:28,558 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2019-08-05 12:16:28,558 INFO L138 SettingsManager]: * Size of a code block=SequenceOfStatements [2019-08-05 12:16:28,559 INFO L138 SettingsManager]: * SMT solver=External_DefaultMode [2019-08-05 12:16:28,559 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2019-08-05 12:16:28,559 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2019-08-05 12:16:28,560 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2019-08-05 12:16:28,560 INFO L138 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles [2019-08-05 12:16:28,560 INFO L138 SettingsManager]: * Trace refinement strategy=TAIPAN [2019-08-05 12:16:28,560 INFO L138 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2019-08-05 12:16:28,560 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2019-08-05 12:16:28,561 INFO L138 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2019-08-05 12:16:28,561 INFO L138 SettingsManager]: * Abstract interpretation Mode=USE_PREDICATES [2019-08-05 12:16:28,612 INFO L81 nceAwareModelManager]: Repository-Root is: /tmp [2019-08-05 12:16:28,627 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2019-08-05 12:16:28,631 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2019-08-05 12:16:28,633 INFO L271 PluginConnector]: Initializing Boogie PL CUP Parser... [2019-08-05 12:16:28,634 INFO L275 PluginConnector]: Boogie PL CUP Parser initialized [2019-08-05 12:16:28,636 INFO L428 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/programs/scalable/CTR_CounterExp-4bit.bpl [2019-08-05 12:16:28,636 INFO L110 BoogieParser]: Parsing: '/storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/programs/scalable/CTR_CounterExp-4bit.bpl' [2019-08-05 12:16:28,672 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2019-08-05 12:16:28,673 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2019-08-05 12:16:28,674 INFO L113 PluginConnector]: ------------------------Boogie Procedure Inliner---------------------------- [2019-08-05 12:16:28,674 INFO L271 PluginConnector]: Initializing Boogie Procedure Inliner... [2019-08-05 12:16:28,674 INFO L275 PluginConnector]: Boogie Procedure Inliner initialized [2019-08-05 12:16:28,690 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Procedure Inliner for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,698 INFO L185 PluginConnector]: Executing the observer Inliner from plugin Boogie Procedure Inliner for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,704 WARN L165 Inliner]: Program contained no entry procedure! [2019-08-05 12:16:28,704 WARN L168 Inliner]: Missing entry procedures: [ULTIMATE.start] [2019-08-05 12:16:28,704 WARN L175 Inliner]: Fallback enabled. All procedures will be processed. [2019-08-05 12:16:28,706 INFO L132 PluginConnector]: ------------------------ END Boogie Procedure Inliner---------------------------- [2019-08-05 12:16:28,707 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2019-08-05 12:16:28,707 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2019-08-05 12:16:28,708 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2019-08-05 12:16:28,718 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,719 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,719 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,720 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,723 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,727 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,728 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... [2019-08-05 12:16:28,730 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2019-08-05 12:16:28,730 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2019-08-05 12:16:28,731 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2019-08-05 12:16:28,731 INFO L275 PluginConnector]: RCFGBuilder initialized [2019-08-05 12:16:28,732 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.boogie.parser AST 05.08 12:16:28" (1/1) ... No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3 Starting monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null) Waiting until toolchain timeout for monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2019-08-05 12:16:28,792 INFO L124 BoogieDeclarations]: Specification and implementation of procedure ThreeBitCounter given in one single declaration [2019-08-05 12:16:28,792 INFO L130 BoogieDeclarations]: Found specification of procedure ThreeBitCounter [2019-08-05 12:16:28,792 INFO L138 BoogieDeclarations]: Found implementation of procedure ThreeBitCounter [2019-08-05 12:16:29,199 INFO L275 CfgBuilder]: Using library mode [2019-08-05 12:16:29,199 INFO L283 CfgBuilder]: Removed 0 assume(true) statements. [2019-08-05 12:16:29,200 INFO L202 PluginConnector]: Adding new model CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 05.08 12:16:29 BoogieIcfgContainer [2019-08-05 12:16:29,201 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2019-08-05 12:16:29,201 INFO L113 PluginConnector]: ------------------------Abstract Interpretation---------------------------- [2019-08-05 12:16:29,201 INFO L271 PluginConnector]: Initializing Abstract Interpretation... [2019-08-05 12:16:29,202 INFO L275 PluginConnector]: Abstract Interpretation initialized [2019-08-05 12:16:29,203 INFO L185 PluginConnector]: Executing the observer AbstractInterpretationRcfgObserver from plugin Abstract Interpretation for "CTR_CounterExp-4bit.bpl de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 05.08 12:16:29" (1/1) ... [2019-08-05 12:16:29,259 INFO L101 FixpointEngine]: Starting fixpoint engine with domain CompoundDomain (maxUnwinding=3, maxParallelStates=2) [2019-08-05 12:16:29,519 INFO L263 AbstractInterpreter]: Some error location(s) were reachable [2019-08-05 12:16:29,541 INFO L272 AbstractInterpreter]: Visited 20 different actions 102 times. Merged at 15 different actions 41 times. Widened at 3 different actions 3 times. Performed 408 root evaluator evaluations with a maximum evaluation depth of 4. Performed 408 inverse root evaluator evaluations with a maximum inverse evaluation depth of 4. Found 29 fixpoints after 12 different actions. Largest state had 0 variables. [2019-08-05 12:16:29,542 INFO L132 PluginConnector]: ------------------------ END Abstract Interpretation---------------------------- [2019-08-05 12:16:29,545 INFO L168 Benchmark]: Toolchain (without parser) took 870.30 ms. Allocated memory is still 133.2 MB. Free memory was 107.2 MB in the beginning and 85.1 MB in the end (delta: 22.1 MB). Peak memory consumption was 22.1 MB. Max. memory is 7.1 GB. [2019-08-05 12:16:29,546 INFO L168 Benchmark]: Boogie PL CUP Parser took 0.26 ms. Allocated memory is still 133.2 MB. Free memory was 108.4 MB in the beginning and 108.2 MB in the end (delta: 209.7 kB). Peak memory consumption was 209.7 kB. Max. memory is 7.1 GB. [2019-08-05 12:16:29,547 INFO L168 Benchmark]: Boogie Procedure Inliner took 32.80 ms. Allocated memory is still 133.2 MB. Free memory was 107.2 MB in the beginning and 105.2 MB in the end (delta: 2.0 MB). Peak memory consumption was 2.0 MB. Max. memory is 7.1 GB. [2019-08-05 12:16:29,548 INFO L168 Benchmark]: Boogie Preprocessor took 22.83 ms. Allocated memory is still 133.2 MB. Free memory was 105.2 MB in the beginning and 104.1 MB in the end (delta: 1.1 MB). Peak memory consumption was 1.1 MB. Max. memory is 7.1 GB. [2019-08-05 12:16:29,549 INFO L168 Benchmark]: RCFGBuilder took 470.26 ms. Allocated memory is still 133.2 MB. Free memory was 104.1 MB in the beginning and 94.0 MB in the end (delta: 10.1 MB). Peak memory consumption was 10.1 MB. Max. memory is 7.1 GB. [2019-08-05 12:16:29,550 INFO L168 Benchmark]: Abstract Interpretation took 340.49 ms. Allocated memory is still 133.2 MB. Free memory was 93.8 MB in the beginning and 85.1 MB in the end (delta: 8.7 MB). Peak memory consumption was 8.7 MB. Max. memory is 7.1 GB. [2019-08-05 12:16:29,555 INFO L335 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * Boogie PL CUP Parser took 0.26 ms. Allocated memory is still 133.2 MB. Free memory was 108.4 MB in the beginning and 108.2 MB in the end (delta: 209.7 kB). Peak memory consumption was 209.7 kB. Max. memory is 7.1 GB. * Boogie Procedure Inliner took 32.80 ms. Allocated memory is still 133.2 MB. Free memory was 107.2 MB in the beginning and 105.2 MB in the end (delta: 2.0 MB). Peak memory consumption was 2.0 MB. Max. memory is 7.1 GB. * Boogie Preprocessor took 22.83 ms. Allocated memory is still 133.2 MB. Free memory was 105.2 MB in the beginning and 104.1 MB in the end (delta: 1.1 MB). Peak memory consumption was 1.1 MB. Max. memory is 7.1 GB. * RCFGBuilder took 470.26 ms. Allocated memory is still 133.2 MB. Free memory was 104.1 MB in the beginning and 94.0 MB in the end (delta: 10.1 MB). Peak memory consumption was 10.1 MB. Max. memory is 7.1 GB. * Abstract Interpretation took 340.49 ms. Allocated memory is still 133.2 MB. Free memory was 93.8 MB in the beginning and 85.1 MB in the end (delta: 8.7 MB). Peak memory consumption was 8.7 MB. Max. memory is 7.1 GB. * Results from de.uni_freiburg.informatik.ultimate.plugins.analysis.abstractinterpretationv2: - UnprovableResult [Line: 46]: Unable to prove that assertion always holds Unable to prove that assertion always holds Reason: abstract domain could reach this error location. Possible FailurePath: [L5] of := false; [L6] x0 := false; [L7] x1 := false; [L8] x2 := false; [L9] x3 := false; [L11] COND TRUE of == false [L12] COND FALSE !(x0 == true) [L16] x0 := true; [L18] COND FALSE !(of == true) [L27] COND FALSE !(of == true) [L36] COND FALSE !(of == true) [L11] COND TRUE of == false [L12] COND TRUE x0 == true [L13] x0 := false; [L14] of := true; [L18] COND TRUE of == true [L19] COND FALSE !(x1 == true) [L23] x1 := true; [L24] of := false; [L27] COND FALSE !(of == true) [L36] COND FALSE !(of == true) [L11] COND TRUE of == false [L12] COND FALSE !(x0 == true) [L16] x0 := true; [L18] COND TRUE of == true [L19] COND TRUE x1 == true [L20] x1 := false; [L27] COND TRUE of == true [L28] COND FALSE !(x2 == true) [L32] x2 := true; [L33] of := false; [L36] COND FALSE !(of == true) [L11] COND TRUE of == false [L12] COND FALSE !(x0 == true) [L16] x0 := true; [L18] COND TRUE of == true [L19] COND TRUE x1 == true [L20] x1 := false; [L27] COND TRUE of == true [L28] COND TRUE x2 == true [L29] x2 := false; [L36] COND TRUE of == true [L37] COND FALSE !(x3 == true) [L41] x3 := true; [L42] of := false; [L11] COND TRUE of == false [L12] COND TRUE x0 == true [L13] x0 := false; [L14] of := true; [L18] COND TRUE of == true [L19] COND TRUE x1 == true [L20] x1 := false; [L27] COND TRUE of == true [L28] COND TRUE x2 == true [L29] x2 := false; [L36] COND TRUE of == true [L37] COND TRUE x3 == true [L38] x3 := false; [L11] COND FALSE !(of == false) [L46] assert !x0 && !x1 && !x2 && !x3; RESULT: Ultimate could not prove your program: unable to determine feasibility of some traces Received shutdown request...