com.ibm.wala.core.util.ref.ReferenceCleanser.clearSoftCaches() throws java.util.ConcurrentModificationException #1377
Description
From time to time, I am seeing the below failure:
java.util.ConcurrentModificationException
at java.base/java.util.LinkedHashMap$LinkedHashIterator.nextNode(LinkedHashMap.java:719)
at java.base/java.util.LinkedHashMap$LinkedValueIterator.next(LinkedHashMap.java:746)
at com.ibm.wala.util.collections.MapIterator.next(MapIterator.java:34)
at com.ibm.wala.core.util.ref.ReferenceCleanser.clearSoftCaches(ReferenceCleanser.java:77)
at com.ibm.wala.ipa.callgraph.propagation.SSAPropagationCallGraphBuilder.unconditionallyAddConstraintsFromNode(SSAPropagationCallGraphBuilder.java:202)
at com.ibm.wala.ipa.callgraph.propagation.SSAPropagationCallGraphBuilder.addConstraintsFromNode(SSAPropagationCallGraphBuilder.java:191)
at com.ibm.wala.ipa.callgraph.propagation.PropagationCallGraphBuilder.addConstraintsFromNewNodes(PropagationCallGraphBuilder.java:308)
at com.ibm.wala.ipa.callgraph.propagation.StandardSolver.solve(StandardSolver.java:53)
at com.ibm.wala.ipa.callgraph.propagation.PropagationCallGraphBuilder.makeCallGraph(PropagationCallGraphBuilder.java:248)
at com.ibm.wala.ipa.callgraph.propagation.PropagationCallGraphBuilder.makeCallGraph(PropagationCallGraphBuilder.java:191)
at com.ibm.wala.cast.python.ml.test.TestTensorflow2Model.test(TestTensorflow2Model.java:1504)
at com.ibm.wala.cast.python.ml.test.TestTensorflow2Model.testDataset31(TestTensorflow2Model.java:1059)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
at org.junit.runners.BlockJUnit4ClassRunner$1.evaluate(BlockJUnit4ClassRunner.java:100)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:103)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:63)
at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
at org.apache.maven.surefire.junitcore.pc.Scheduler$1.run(Scheduler.java:398)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:829)
I believe the iteration causing the problem is happening here:
The involved IClassHierarchy is coming from here:
Which is coming from here:
The corresponding (static) field is here:
Perhaps there needs to be some synchronization around this (static) field?