ADDITIONAL SYSTEM INFORMATION :
$ java -version
openjdk version "12" 2019-03-19
OpenJDK Runtime Environment (build 12+33)
OpenJDK 64-Bit Server VM (build 12+33, mixed mode, sharing)

$ uname -a
Darwin Davids-MacBook-Pro-3.local 18.2.0 Darwin Kernel Version 18.2.0: Mon Nov 12 20:24:46 PST 2018; root:xnu-4903.231.4~2/RELEASE_X86_64 x86_64

Compiling this using `./gradlew :server:compileTestJava` run from the project root.

A DESCRIPTION OF THE PROBLEM :
The following change to Elasticsearch results in javac throwing a NullPointerException. The preceding commit compiles successfully.

https://github.com/DaveCTurner/elasticsearch/commit/6b26154b705c0fb05920138a5758f2d5388c6c15


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Check out the commit above:

https://github.com/DaveCTurner/elasticsearch/commit/6b26154b705c0fb05920138a5758f2d5388c6c15

Run `./gradlew :server:compileTestJava` from the project root.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Expect successful compilation.
ACTUAL -
Compilation fails with the following messages:

An exception has occurred in the compiler (12). Please file a bug against the Java compiler via the Java bug reporting page (http://bugreport.java.com) after checking the Bug Database (http://bugs.java.com) for duplicates. Include your program and the following diagnostic in your report. Thank you.
java.lang.NullPointerException
at jdk.compiler/com.sun.tools.javac.code.Symbol$ClassSymbol.isSubClass(Symbol.java:1308)
at jdk.compiler/com.sun.tools.javac.comp.Lower.accessClass(Lower.java:1095)
at jdk.compiler/com.sun.tools.javac.comp.Lower.accessSymbol(Lower.java:966)
at jdk.compiler/com.sun.tools.javac.comp.Lower.access(Lower.java:1211)
at jdk.compiler/com.sun.tools.javac.comp.Lower.visitSelect(Lower.java:3718)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:2189)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2087)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2098)
at jdk.compiler/com.sun.tools.javac.comp.Lower.boxArgs(Lower.java:2835)
at jdk.compiler/com.sun.tools.javac.comp.Lower.visitNewClass(Lower.java:2575)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCNewClass.accept(JCTree.java:1764)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2087)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2098)
at jdk.compiler/com.sun.tools.javac.comp.Lower.visitReturn(Lower.java:3359)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCReturn.accept(JCTree.java:1621)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2087)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:70)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.visitBlock(TreeTranslator.java:167)
at jdk.compiler/com.sun.tools.javac.comp.Lower.visitBlock(Lower.java:3332)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:1026)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2087)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.visitMethodDef(TreeTranslator.java:150)
at jdk.compiler/com.sun.tools.javac.comp.Lower.visitMethodDefInternal(Lower.java:2540)
at jdk.compiler/com.sun.tools.javac.comp.Lower.visitMethodDef(Lower.java:2452)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:872)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2087)
at jdk.compiler/com.sun.tools.javac.comp.Lower.visitClassDef(Lower.java:2225)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:780)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2087)
at jdk.compiler/com.sun.tools.javac.comp.Lower.visitClassDef(Lower.java:2225)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:780)
at jdk.compiler/com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2087)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translate(Lower.java:2106)
at jdk.compiler/com.sun.tools.javac.comp.Lower.translateTopLevelClass(Lower.java:3795)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1579)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1432)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1516)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1432)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:973)
at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.lambda$doCall$0(JavacTaskImpl.java:104)
at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.handleExceptions(JavacTaskImpl.java:147)
at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.doCall(JavacTaskImpl.java:100)
at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.call(JavacTaskImpl.java:94)
at org.gradle.api.internal.tasks.compile.AnnotationProcessingCompileTask.call(AnnotationProcessingCompileTask.java:92)
at org.gradle.api.internal.tasks.compile.ResourceCleaningCompilationTask.call(ResourceCleaningCompilationTask.java:57)
at org.gradle.api.internal.tasks.compile.JdkJavaCompiler.execute(JdkJavaCompiler.java:50)
at org.gradle.api.internal.tasks.compile.JdkJavaCompiler.execute(JdkJavaCompiler.java:36)
at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.delegateAndHandleErrors(NormalizingJavaCompiler.java:100)
at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:52)
at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:38)
at org.gradle.api.internal.tasks.compile.AnnotationProcessorDiscoveringCompiler.execute(AnnotationProcessorDiscoveringCompiler.java:51)
at org.gradle.api.internal.tasks.compile.AnnotationProcessorDiscoveringCompiler.execute(AnnotationProcessorDiscoveringCompiler.java:37)
at org.gradle.api.internal.tasks.compile.incremental.SelectiveCompiler.execute(SelectiveCompiler.java:78)
at org.gradle.api.internal.tasks.compile.incremental.SelectiveCompiler.execute(SelectiveCompiler.java:37)
at org.gradle.api.internal.tasks.compile.incremental.IncrementalResultStoringCompiler.execute(IncrementalResultStoringCompiler.java:59)
at org.gradle.api.internal.tasks.compile.incremental.IncrementalResultStoringCompiler.execute(IncrementalResultStoringCompiler.java:43)
at org.gradle.api.internal.tasks.compile.CompileJavaBuildOperationReportingCompiler$2.call(CompileJavaBuildOperationReportingCompiler.java:59)
at org.gradle.api.internal.tasks.compile.CompileJavaBuildOperationReportingCompiler$2.call(CompileJavaBuildOperationReportingCompiler.java:51)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:416)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:406)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:102)
at org.gradle.internal.operations.DelegatingBuildOperationExecutor.call(DelegatingBuildOperationExecutor.java:36)
at org.gradle.api.internal.tasks.compile.CompileJavaBuildOperationReportingCompiler.execute(CompileJavaBuildOperationReportingCompiler.java:51)
at org.gradle.api.tasks.compile.JavaCompile.performCompilation(JavaCompile.java:154)
at org.gradle.api.tasks.compile.JavaCompile.compile(JavaCompile.java:122)
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:567)
at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:103)
at org.gradle.api.internal.project.taskfactory.IncrementalTaskAction.doExecute(IncrementalTaskAction.java:73)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:41)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:28)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$4.run(ExecuteActionsTaskExecuter.java:338)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:402)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:394)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:92)
at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:327)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:312)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.access$200(ExecuteActionsTaskExecuter.java:75)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$TaskExecution.execute(ExecuteActionsTaskExecuter.java:158)
at org.gradle.internal.execution.impl.steps.ExecuteStep.execute(ExecuteStep.java:46)
at org.gradle.internal.execution.impl.steps.CancelExecutionStep.execute(CancelExecutionStep.java:34)
at org.gradle.internal.execution.impl.steps.TimeoutStep.executeWithoutTimeout(TimeoutStep.java:69)
at org.gradle.internal.execution.impl.steps.TimeoutStep.execute(TimeoutStep.java:49)
at org.gradle.internal.execution.impl.steps.CatchExceptionStep.execute(CatchExceptionStep.java:34)
at org.gradle.internal.execution.impl.steps.CreateOutputsStep.execute(CreateOutputsStep.java:49)
at org.gradle.internal.execution.impl.steps.SnapshotOutputStep.execute(SnapshotOutputStep.java:42)
at org.gradle.internal.execution.impl.steps.SnapshotOutputStep.execute(SnapshotOutputStep.java:28)
at org.gradle.internal.execution.impl.steps.CacheStep.executeWithoutCache(CacheStep.java:133)
at org.gradle.internal.execution.impl.steps.CacheStep.lambda$execute$5(CacheStep.java:83)
at java.base/java.util.Optional.orElseGet(Optional.java:369)
at org.gradle.internal.execution.impl.steps.CacheStep.execute(CacheStep.java:82)
at org.gradle.internal.execution.impl.steps.CacheStep.execute(CacheStep.java:37)
at org.gradle.internal.execution.impl.steps.PrepareCachingStep.execute(PrepareCachingStep.java:33)
at org.gradle.internal.execution.impl.steps.StoreSnapshotsStep.execute(StoreSnapshotsStep.java:38)
at org.gradle.internal.execution.impl.steps.StoreSnapshotsStep.execute(StoreSnapshotsStep.java:23)
at org.gradle.internal.execution.impl.steps.SkipUpToDateStep.executeBecause(SkipUpToDateStep.java:95)
at org.gradle.internal.execution.impl.steps.SkipUpToDateStep.lambda$execute$0(SkipUpToDateStep.java:88)
at java.base/java.util.Optional.map(Optional.java:265)
at org.gradle.internal.execution.impl.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:52)
at org.gradle.internal.execution.impl.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:36)
at org.gradle.internal.execution.impl.DefaultWorkExecutor.execute(DefaultWorkExecutor.java:34)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:109)
at org.gradle.api.internal.tasks.execution.ResolveIncrementalChangesTaskExecuter.execute(ResolveIncrementalChangesTaskExecuter.java:84)
at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:91)
at org.gradle.api.internal.tasks.execution.FinishSnapshotTaskInputsBuildOperationTaskExecuter.execute(FinishSnapshotTaskInputsBuildOperationTaskExecuter.java:51)
at org.gradle.api.internal.tasks.execution.ResolveBuildCacheKeyExecuter.execute(ResolveBuildCacheKeyExecuter.java:102)
at org.gradle.api.internal.tasks.execution.ResolveBeforeExecutionStateTaskExecuter.execute(ResolveBeforeExecutionStateTaskExecuter.java:74)
at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:109)
at org.gradle.api.internal.tasks.execution.ResolveBeforeExecutionOutputsTaskExecuter.execute(ResolveBeforeExecutionOutputsTaskExecuter.java:67)
at org.gradle.api.internal.tasks.execution.StartSnapshotTaskInputsBuildOperationTaskExecuter.execute(StartSnapshotTaskInputsBuildOperationTaskExecuter.java:52)
at org.gradle.api.internal.tasks.execution.ResolveAfterPreviousExecutionStateTaskExecuter.execute(ResolveAfterPreviousExecutionStateTaskExecuter.java:46)
at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:93)
at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:45)
at org.gradle.api.internal.tasks.execution.ResolveTaskExecutionModeExecuter.execute(ResolveTaskExecutionModeExecuter.java:94)
at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:57)
at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:56)
at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:36)
at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.executeTask(EventFiringTaskExecuter.java:63)
at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:49)
at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:46)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:416)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:406)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:102)
at org.gradle.internal.operations.DelegatingBuildOperationExecutor.call(DelegatingBuildOperationExecutor.java:36)
at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:46)
at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:43)
at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:355)
at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:343)
at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:336)
at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:322)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:134)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:129)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:202)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.executeNextNode(DefaultPlanExecutor.java:193)
at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:129)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
at java.base/java.lang.Thread.run(Thread.java:835)

---------- BEGIN SOURCE ----------
Apologies, Elasticsearch is quite a large project and this code has rather a lot of dependencies, so I have been unable to isolate this down to a simpler test case.
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Use an anonymous class instead of a lambda.

FREQUENCY : always