java -Xmx8000000000 -Xss4m -jar ./plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -data @noDefault -ultimatedata ./data -tc ../../../trunk/examples/toolchains/AbstractInterpretationC.xml -s ../../../trunk/examples/settings/ai/svcomp-Reach-32bit-Automizer_Default+AIv2_INT.epf -i ../../../trunk/examples/svcomp/recursive-simple/fibo_2calls_6-2.c -------------------------------------------------------------------------------- This is Ultimate 0.1.24-112bae1 [2019-09-11 16:32:59,019 INFO L177 SettingsManager]: Resetting all preferences to default values... [2019-09-11 16:32:59,022 INFO L181 SettingsManager]: Resetting UltimateCore preferences to default values [2019-09-11 16:32:59,040 INFO L184 SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring... [2019-09-11 16:32:59,040 INFO L181 SettingsManager]: Resetting Boogie Preprocessor preferences to default values [2019-09-11 16:32:59,042 INFO L181 SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values [2019-09-11 16:32:59,044 INFO L181 SettingsManager]: Resetting Abstract Interpretation preferences to default values [2019-09-11 16:32:59,057 INFO L181 SettingsManager]: Resetting LassoRanker preferences to default values [2019-09-11 16:32:59,058 INFO L181 SettingsManager]: Resetting Reaching Definitions preferences to default values [2019-09-11 16:32:59,059 INFO L181 SettingsManager]: Resetting SyntaxChecker preferences to default values [2019-09-11 16:32:59,060 INFO L181 SettingsManager]: Resetting Sifa preferences to default values [2019-09-11 16:32:59,061 INFO L184 SettingsManager]: Büchi Program Product provides no preferences, ignoring... [2019-09-11 16:32:59,061 INFO L181 SettingsManager]: Resetting LTL2Aut preferences to default values [2019-09-11 16:32:59,062 INFO L181 SettingsManager]: Resetting PEA to Boogie preferences to default values [2019-09-11 16:32:59,063 INFO L181 SettingsManager]: Resetting BlockEncodingV2 preferences to default values [2019-09-11 16:32:59,064 INFO L181 SettingsManager]: Resetting ChcToBoogie preferences to default values [2019-09-11 16:32:59,065 INFO L181 SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values [2019-09-11 16:32:59,066 INFO L181 SettingsManager]: Resetting BuchiAutomizer preferences to default values [2019-09-11 16:32:59,067 INFO L181 SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values [2019-09-11 16:32:59,069 INFO L181 SettingsManager]: Resetting CodeCheck preferences to default values [2019-09-11 16:32:59,071 INFO L181 SettingsManager]: Resetting InvariantSynthesis preferences to default values [2019-09-11 16:32:59,071 INFO L181 SettingsManager]: Resetting RCFGBuilder preferences to default values [2019-09-11 16:32:59,073 INFO L181 SettingsManager]: Resetting Referee preferences to default values [2019-09-11 16:32:59,073 INFO L181 SettingsManager]: Resetting TraceAbstraction preferences to default values [2019-09-11 16:32:59,075 INFO L184 SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring... [2019-09-11 16:32:59,075 INFO L184 SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring... [2019-09-11 16:32:59,076 INFO L181 SettingsManager]: Resetting TreeAutomizer preferences to default values [2019-09-11 16:32:59,076 INFO L181 SettingsManager]: Resetting IcfgToChc preferences to default values [2019-09-11 16:32:59,077 INFO L181 SettingsManager]: Resetting IcfgTransformer preferences to default values [2019-09-11 16:32:59,078 INFO L184 SettingsManager]: ReqToTest provides no preferences, ignoring... [2019-09-11 16:32:59,078 INFO L181 SettingsManager]: Resetting Boogie Printer preferences to default values [2019-09-11 16:32:59,079 INFO L181 SettingsManager]: Resetting ChcSmtPrinter preferences to default values [2019-09-11 16:32:59,080 INFO L181 SettingsManager]: Resetting ReqPrinter preferences to default values [2019-09-11 16:32:59,080 INFO L181 SettingsManager]: Resetting Witness Printer preferences to default values [2019-09-11 16:32:59,081 INFO L184 SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring... [2019-09-11 16:32:59,082 INFO L181 SettingsManager]: Resetting CDTParser preferences to default values [2019-09-11 16:32:59,084 INFO L184 SettingsManager]: AutomataScriptParser provides no preferences, ignoring... [2019-09-11 16:32:59,084 INFO L184 SettingsManager]: ReqParser provides no preferences, ignoring... [2019-09-11 16:32:59,084 INFO L181 SettingsManager]: Resetting SmtParser preferences to default values [2019-09-11 16:32:59,085 INFO L181 SettingsManager]: Resetting Witness Parser preferences to default values [2019-09-11 16:32:59,086 INFO L188 SettingsManager]: Finished resetting all preferences to default values... [2019-09-11 16:32:59,087 INFO L101 SettingsManager]: Beginning loading settings from /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/settings/ai/svcomp-Reach-32bit-Automizer_Default+AIv2_INT.epf [2019-09-11 16:32:59,115 INFO L113 SettingsManager]: Loading preferences was successful [2019-09-11 16:32:59,116 INFO L115 SettingsManager]: Preferences different from defaults after loading the file: [2019-09-11 16:32:59,116 INFO L136 SettingsManager]: Preferences of UltimateCore differ from their defaults: [2019-09-11 16:32:59,117 INFO L138 SettingsManager]: * Log level for plugins=info [2019-09-11 16:32:59,118 INFO L136 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2019-09-11 16:32:59,118 INFO L138 SettingsManager]: * User list type=DISABLED [2019-09-11 16:32:59,118 INFO L138 SettingsManager]: * Ignore calls to and inside polymorphic procedures=false [2019-09-11 16:32:59,118 INFO L138 SettingsManager]: * Ignore calls to recursive procedures=false [2019-09-11 16:32:59,119 INFO L136 SettingsManager]: Preferences of Abstract Interpretation differ from their defaults: [2019-09-11 16:32:59,119 INFO L138 SettingsManager]: * Abstract domain=IntervalDomain [2019-09-11 16:32:59,121 INFO L136 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2019-09-11 16:32:59,121 INFO L138 SettingsManager]: * sizeof long=4 [2019-09-11 16:32:59,122 INFO L138 SettingsManager]: * sizeof POINTER=4 [2019-09-11 16:32:59,122 INFO L138 SettingsManager]: * Check division by zero=IGNORE [2019-09-11 16:32:59,122 INFO L138 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2019-09-11 16:32:59,122 INFO L138 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2019-09-11 16:32:59,123 INFO L138 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2019-09-11 16:32:59,123 INFO L138 SettingsManager]: * sizeof long double=12 [2019-09-11 16:32:59,123 INFO L138 SettingsManager]: * Check if freed pointer was valid=false [2019-09-11 16:32:59,123 INFO L138 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2019-09-11 16:32:59,124 INFO L136 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2019-09-11 16:32:59,124 INFO L138 SettingsManager]: * Remove goto edges from RCFG=true [2019-09-11 16:32:59,124 INFO L138 SettingsManager]: * Size of a code block=SequenceOfStatements [2019-09-11 16:32:59,124 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2019-09-11 16:32:59,125 INFO L136 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2019-09-11 16:32:59,125 INFO L138 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2019-09-11 16:32:59,125 INFO L138 SettingsManager]: * Trace refinement strategy=TAIPAN [2019-09-11 16:32:59,125 INFO L138 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2019-09-11 16:32:59,126 INFO L138 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2019-09-11 16:32:59,126 INFO L138 SettingsManager]: * Abstract interpretation Mode=USE_PREDICATES [2019-09-11 16:32:59,167 INFO L81 nceAwareModelManager]: Repository-Root is: /tmp [2019-09-11 16:32:59,178 INFO L258 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2019-09-11 16:32:59,181 INFO L214 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2019-09-11 16:32:59,182 INFO L271 PluginConnector]: Initializing CDTParser... [2019-09-11 16:32:59,185 INFO L275 PluginConnector]: CDTParser initialized [2019-09-11 16:32:59,186 INFO L428 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/recursive-simple/fibo_2calls_6-2.c [2019-09-11 16:32:59,250 INFO L220 CDTParser]: Created temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/4f93c5fb1/fe9dc58b68684d4d8c62f8e372eafb76/FLAG059907f33 [2019-09-11 16:32:59,816 INFO L306 CDTParser]: Found 1 translation units. [2019-09-11 16:32:59,817 INFO L160 CDTParser]: Scanning /storage/repos/ultimate/trunk/examples/svcomp/recursive-simple/fibo_2calls_6-2.c [2019-09-11 16:32:59,823 INFO L349 CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/4f93c5fb1/fe9dc58b68684d4d8c62f8e372eafb76/FLAG059907f33 [2019-09-11 16:33:00,072 INFO L357 CDTParser]: Successfully deleted /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/4f93c5fb1/fe9dc58b68684d4d8c62f8e372eafb76 [2019-09-11 16:33:00,084 INFO L296 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2019-09-11 16:33:00,087 INFO L131 ToolchainWalker]: Walking toolchain with 4 elements. [2019-09-11 16:33:00,088 INFO L113 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2019-09-11 16:33:00,089 INFO L271 PluginConnector]: Initializing CACSL2BoogieTranslator... [2019-09-11 16:33:00,092 INFO L275 PluginConnector]: CACSL2BoogieTranslator initialized [2019-09-11 16:33:00,093 INFO L185 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,097 INFO L205 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@bd9554 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00, skipping insertion in model container [2019-09-11 16:33:00,097 INFO L185 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,105 INFO L142 MainTranslator]: Starting translation in SV-COMP mode [2019-09-11 16:33:00,126 INFO L173 MainTranslator]: Built tables and reachable declarations [2019-09-11 16:33:00,288 INFO L206 PostProcessor]: Analyzing one entry point: main [2019-09-11 16:33:00,293 INFO L188 MainTranslator]: Completed pre-run [2019-09-11 16:33:00,313 INFO L206 PostProcessor]: Analyzing one entry point: main [2019-09-11 16:33:00,329 INFO L192 MainTranslator]: Completed translation [2019-09-11 16:33:00,329 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00 WrapperNode [2019-09-11 16:33:00,330 INFO L132 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2019-09-11 16:33:00,331 INFO L113 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2019-09-11 16:33:00,331 INFO L271 PluginConnector]: Initializing Boogie Preprocessor... [2019-09-11 16:33:00,331 INFO L275 PluginConnector]: Boogie Preprocessor initialized [2019-09-11 16:33:00,441 INFO L185 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,443 INFO L185 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,451 INFO L185 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,451 INFO L185 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,455 INFO L185 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,457 INFO L185 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,458 INFO L185 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,460 INFO L132 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2019-09-11 16:33:00,460 INFO L113 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2019-09-11 16:33:00,461 INFO L271 PluginConnector]: Initializing RCFGBuilder... [2019-09-11 16:33:00,461 INFO L275 PluginConnector]: RCFGBuilder initialized [2019-09-11 16:33:00,462 INFO L185 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 11.09 04:33:00" (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 [2019-09-11 16:33:00,529 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.init [2019-09-11 16:33:00,529 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2019-09-11 16:33:00,529 INFO L138 BoogieDeclarations]: Found implementation of procedure fibo1 [2019-09-11 16:33:00,529 INFO L138 BoogieDeclarations]: Found implementation of procedure fibo2 [2019-09-11 16:33:00,530 INFO L138 BoogieDeclarations]: Found implementation of procedure main [2019-09-11 16:33:00,530 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_int [2019-09-11 16:33:00,530 INFO L130 BoogieDeclarations]: Found specification of procedure __VERIFIER_error [2019-09-11 16:33:00,530 INFO L130 BoogieDeclarations]: Found specification of procedure fibo1 [2019-09-11 16:33:00,530 INFO L130 BoogieDeclarations]: Found specification of procedure fibo2 [2019-09-11 16:33:00,530 INFO L130 BoogieDeclarations]: Found specification of procedure main [2019-09-11 16:33:00,531 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.init [2019-09-11 16:33:00,531 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2019-09-11 16:33:00,730 INFO L278 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2019-09-11 16:33:00,730 INFO L283 CfgBuilder]: Removed 0 assume(true) statements. [2019-09-11 16:33:00,732 INFO L202 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 11.09 04:33:00 BoogieIcfgContainer [2019-09-11 16:33:00,732 INFO L132 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2019-09-11 16:33:00,733 INFO L113 PluginConnector]: ------------------------Abstract Interpretation---------------------------- [2019-09-11 16:33:00,733 INFO L271 PluginConnector]: Initializing Abstract Interpretation... [2019-09-11 16:33:00,733 INFO L275 PluginConnector]: Abstract Interpretation initialized [2019-09-11 16:33:00,734 INFO L185 PluginConnector]: Executing the observer AbstractInterpretationRcfgObserver from plugin Abstract Interpretation for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 11.09 04:33:00" (1/1) ... [2019-09-11 16:33:00,760 INFO L101 FixpointEngine]: Starting fixpoint engine with domain IntervalDomain (maxUnwinding=3, maxParallelStates=2) [2019-09-11 16:33:01,132 INFO L263 AbstractInterpreter]: Some error location(s) were reachable [2019-09-11 16:33:01,167 INFO L272 AbstractInterpreter]: Visited 40 different actions 813 times. Merged at 17 different actions 103 times. Widened at 2 different actions 2 times. Performed 889 root evaluator evaluations with a maximum evaluation depth of 3. Performed 889 inverse root evaluator evaluations with a maximum inverse evaluation depth of 3. Found 8 fixpoints after 6 different actions. Largest state had 5 variables. [2019-09-11 16:33:01,167 INFO L132 PluginConnector]: ------------------------ END Abstract Interpretation---------------------------- [2019-09-11 16:33:01,171 INFO L168 Benchmark]: Toolchain (without parser) took 1083.79 ms. Allocated memory was 140.5 MB in the beginning and 200.3 MB in the end (delta: 59.8 MB). Free memory was 88.9 MB in the beginning and 143.4 MB in the end (delta: -54.5 MB). Peak memory consumption was 5.2 MB. Max. memory is 7.1 GB. [2019-09-11 16:33:01,172 INFO L168 Benchmark]: CDTParser took 0.22 ms. Allocated memory is still 140.5 MB. Free memory was 107.0 MB in the beginning and 106.8 MB in the end (delta: 212.8 kB). Peak memory consumption was 212.8 kB. Max. memory is 7.1 GB. [2019-09-11 16:33:01,173 INFO L168 Benchmark]: CACSL2BoogieTranslator took 241.83 ms. Allocated memory is still 140.5 MB. Free memory was 88.7 MB in the beginning and 79.2 MB in the end (delta: 9.4 MB). Peak memory consumption was 9.4 MB. Max. memory is 7.1 GB. [2019-09-11 16:33:01,174 INFO L168 Benchmark]: Boogie Preprocessor took 129.42 ms. Allocated memory was 140.5 MB in the beginning and 200.3 MB in the end (delta: 59.8 MB). Free memory was 79.2 MB in the beginning and 178.3 MB in the end (delta: -99.1 MB). Peak memory consumption was 11.2 MB. Max. memory is 7.1 GB. [2019-09-11 16:33:01,175 INFO L168 Benchmark]: RCFGBuilder took 271.49 ms. Allocated memory is still 200.3 MB. Free memory was 178.3 MB in the beginning and 165.7 MB in the end (delta: 12.6 MB). Peak memory consumption was 12.6 MB. Max. memory is 7.1 GB. [2019-09-11 16:33:01,176 INFO L168 Benchmark]: Abstract Interpretation took 434.86 ms. Allocated memory is still 200.3 MB. Free memory was 165.1 MB in the beginning and 143.4 MB in the end (delta: 21.7 MB). Peak memory consumption was 21.7 MB. Max. memory is 7.1 GB. [2019-09-11 16:33:01,181 INFO L335 ainManager$Toolchain]: ####################### End [Toolchain 1] ####################### --- Results --- * Results from de.uni_freiburg.informatik.ultimate.core: - StatisticsResult: Toolchain Benchmarks Benchmark results are: * CDTParser took 0.22 ms. Allocated memory is still 140.5 MB. Free memory was 107.0 MB in the beginning and 106.8 MB in the end (delta: 212.8 kB). Peak memory consumption was 212.8 kB. Max. memory is 7.1 GB. * CACSL2BoogieTranslator took 241.83 ms. Allocated memory is still 140.5 MB. Free memory was 88.7 MB in the beginning and 79.2 MB in the end (delta: 9.4 MB). Peak memory consumption was 9.4 MB. Max. memory is 7.1 GB. * Boogie Preprocessor took 129.42 ms. Allocated memory was 140.5 MB in the beginning and 200.3 MB in the end (delta: 59.8 MB). Free memory was 79.2 MB in the beginning and 178.3 MB in the end (delta: -99.1 MB). Peak memory consumption was 11.2 MB. Max. memory is 7.1 GB. * RCFGBuilder took 271.49 ms. Allocated memory is still 200.3 MB. Free memory was 178.3 MB in the beginning and 165.7 MB in the end (delta: 12.6 MB). Peak memory consumption was 12.6 MB. Max. memory is 7.1 GB. * Abstract Interpretation took 434.86 ms. Allocated memory is still 200.3 MB. Free memory was 165.1 MB in the beginning and 143.4 MB in the end (delta: 21.7 MB). Peak memory consumption was 21.7 MB. Max. memory is 7.1 GB. * Results from de.uni_freiburg.informatik.ultimate.plugins.analysis.abstractinterpretationv2: - UnprovableResult [Line: 39]: Unable to prove that call of __VERIFIER_error() unreachable Unable to prove that call of __VERIFIER_error() unreachable Reason: abstract domain could reach this error location. Possible FailurePath: [L36] int x = 6; [L37] CALL, EXPR fibo1(x) [L8] COND FALSE !(n < 1) [L10] COND FALSE !(n == 1) [L13] CALL, EXPR fibo2(n-1) [L18] COND FALSE !(n < 1) [L20] COND FALSE !(n == 1) [L23] CALL, EXPR fibo1(n-1) [L8] COND FALSE !(n < 1) [L10] COND FALSE !(n == 1) [L13] CALL, EXPR fibo2(n-1) [L18] COND FALSE !(n < 1) [L20] COND FALSE !(n == 1) [L23] CALL, EXPR fibo1(n-1) [L8] COND FALSE !(n < 1) [L10] COND FALSE !(n == 1) [L13] CALL, EXPR fibo2(n-1) [L18] COND FALSE !(n < 1) [L20] COND TRUE n == 1 [L21] return 1; [L13] RET, EXPR fibo2(n-1) [L13] CALL, EXPR fibo2(n-2) [L18] COND TRUE n < 1 [L19] return 0; [L13] RET, EXPR fibo2(n-2) [L13] return fibo2(n-1) + fibo2(n-2); [L23] RET, EXPR fibo1(n-1) [L23] CALL, EXPR fibo1(n-2) [L8] COND FALSE !(n < 1) [L10] COND TRUE n == 1 [L11] return 1; [L23] RET, EXPR fibo1(n-2) [L23] return fibo1(n-1) + fibo1(n-2); [L13] RET, EXPR fibo2(n-1) [L13] CALL, EXPR fibo2(n-2) [L18] COND FALSE !(n < 1) [L20] COND FALSE !(n == 1) [L23] CALL, EXPR fibo1(n-1) [L8] COND FALSE !(n < 1) [L10] COND TRUE n == 1 [L11] return 1; [L23] RET, EXPR fibo1(n-1) [L23] CALL, EXPR fibo1(n-2) [L8] COND TRUE n < 1 [L9] return 0; [L23] RET, EXPR fibo1(n-2) [L23] return fibo1(n-1) + fibo1(n-2); [L13] RET, EXPR fibo2(n-2) [L13] return fibo2(n-1) + fibo2(n-2); [L23] RET, EXPR fibo1(n-1) [L23] CALL, EXPR fibo1(n-2) [L8] COND FALSE !(n < 1) [L10] COND FALSE !(n == 1) [L13] CALL, EXPR fibo2(n-1) [L18] COND FALSE !(n < 1) [L20] COND FALSE !(n == 1) [L23] CALL, EXPR fibo1(n-1) [L8] COND FALSE !(n < 1) [L10] COND TRUE n == 1 [L11] return 1; [L23] RET, EXPR fibo1(n-1) [L23] CALL, EXPR fibo1(n-2) [L8] COND TRUE n < 1 [L9] return 0; [L23] RET, EXPR fibo1(n-2) [L23] return fibo1(n-1) + fibo1(n-2); [L13] RET, EXPR fibo2(n-1) [L13] CALL, EXPR fibo2(n-2) [L18] COND FALSE !(n < 1) [L20] COND TRUE n == 1 [L21] return 1; [L13] RET, EXPR fibo2(n-2) [L13] return fibo2(n-1) + fibo2(n-2); [L23] RET, EXPR fibo1(n-2) [L23] return fibo1(n-1) + fibo1(n-2); [L13] RET, EXPR fibo2(n-1) [L13] CALL, EXPR fibo2(n-2) [L18] COND FALSE !(n < 1) [L20] COND FALSE !(n == 1) [L23] CALL, EXPR fibo1(n-1) [L8] COND FALSE !(n < 1) [L10] COND FALSE !(n == 1) [L13] CALL, EXPR fibo2(n-1) [L18] COND FALSE !(n < 1) [L20] COND FALSE !(n == 1) [L23] CALL, EXPR fibo1(n-1) [L8] COND FALSE !(n < 1) [L10] COND TRUE n == 1 [L11] return 1; [L23] RET, EXPR fibo1(n-1) [L23] CALL, EXPR fibo1(n-2) [L8] COND TRUE n < 1 [L9] return 0; [L23] RET, EXPR fibo1(n-2) [L23] return fibo1(n-1) + fibo1(n-2); [L13] RET, EXPR fibo2(n-1) [L13] CALL, EXPR fibo2(n-2) [L18] COND FALSE !(n < 1) [L20] COND TRUE n == 1 [L21] return 1; [L13] RET, EXPR fibo2(n-2) [L13] return fibo2(n-1) + fibo2(n-2); [L23] RET, EXPR fibo1(n-1) [L23] CALL, EXPR fibo1(n-2) [L8] COND FALSE !(n < 1) [L10] COND FALSE !(n == 1) [L13] CALL, EXPR fibo2(n-1) [L18] COND FALSE !(n < 1) [L20] COND TRUE n == 1 [L21] return 1; [L13] RET, EXPR fibo2(n-1) [L13] CALL, EXPR fibo2(n-2) [L18] COND TRUE n < 1 [L19] return 0; [L13] RET, EXPR fibo2(n-2) [L13] return fibo2(n-1) + fibo2(n-2); [L23] RET, EXPR fibo1(n-2) [L23] return fibo1(n-1) + fibo1(n-2); [L13] RET, EXPR fibo2(n-2) [L13] return fibo2(n-1) + fibo2(n-2); [L37] RET, EXPR fibo1(x) [L37] int result = fibo1(x); [L38] COND TRUE result == 8 [L39] __VERIFIER_error() RESULT: Ultimate could not prove your program: unable to determine feasibility of some traces Received shutdown request...