A DESCRIPTION OF THE PROBLEM :
In jshell upon trying to create a self referencing variable with the var keyword jshell crashes. According to the stacktrace this is because of a NullPointerException when trying to infer the type of the variable which is null because it is not defined until now.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Open jshell and enter:

var a = a;

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
An error message, explaining that the variable cannot be created
ACTUAL -
Exception in thread "main" java.lang.InternalError: Exception during analyze - java.lang.NullPointerException: Cannot invoke "com.sun.tools.javac.code.Type.baseType()" because "tree.init.type" is null
        at jdk.jshell/jdk.jshell.TaskFactory$AnalyzeTask.analyze(TaskFactory.java:393)
        at jdk.jshell/jdk.jshell.TaskFactory$AnalyzeTask.<init>(TaskFactory.java:384)
        at jdk.jshell/jdk.jshell.TaskFactory.lambda$analyze$1(TaskFactory.java:177)
        at jdk.jshell/jdk.jshell.TaskFactory.lambda$runTask$4(TaskFactory.java:212)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskPool.getTask(JavacTaskPool.java:193)
        at jdk.jshell/jdk.jshell.TaskFactory.runTask(TaskFactory.java:205)
        at jdk.jshell/jdk.jshell.TaskFactory.analyze(TaskFactory.java:174)
        at jdk.jshell/jdk.jshell.TaskFactory.analyze(TaskFactory.java:160)
        at jdk.jshell/jdk.jshell.TaskFactory.analyze(TaskFactory.java:149)
        at jdk.jshell/jdk.jshell.Eval.trialCompile(Eval.java:735)
        at jdk.jshell/jdk.jshell.Eval.processVariables(Eval.java:326)
        at jdk.jshell/jdk.jshell.Eval.lambda$sourceToSnippets$1(Eval.java:218)
        at jdk.jshell/jdk.jshell.TaskFactory.lambda$parse$6(TaskFactory.java:254)
        at jdk.jshell/jdk.jshell.TaskFactory.lambda$runTask$4(TaskFactory.java:212)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskPool.getTask(JavacTaskPool.java:193)
        at jdk.jshell/jdk.jshell.TaskFactory.runTask(TaskFactory.java:205)
        at jdk.jshell/jdk.jshell.TaskFactory.parse(TaskFactory.java:139)
        at jdk.jshell/jdk.jshell.TaskFactory.parse(TaskFactory.java:239)
        at jdk.jshell/jdk.jshell.Eval.sourceToSnippets(Eval.java:194)
        at jdk.jshell/jdk.jshell.Eval.eval(Eval.java:130)
        at jdk.jshell/jdk.jshell.JShell.eval(JShell.java:493)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.processSource(JShellTool.java:3618)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.processSourceCatchingReset(JShellTool.java:1342)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.processInput(JShellTool.java:1240)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.run(JShellTool.java:1211)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.start(JShellTool.java:995)
        at jdk.jshell/jdk.internal.jshell.tool.JShellToolBuilder.start(JShellToolBuilder.java:261)
        at jdk.jshell/jdk.internal.jshell.tool.JShellToolProvider.main(JShellToolProvider.java:120)
Caused by: java.lang.IllegalStateException: java.lang.NullPointerException: Cannot invoke "com.sun.tools.javac.code.Type.baseType()" because "tree.init.type" is null
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.analyze(JavacTaskImpl.java:383)
        at jdk.jshell/jdk.jshell.TaskFactory$AnalyzeTask.analyze(TaskFactory.java:390)
        ... 27 more
Caused by: java.lang.NullPointerException: Cannot invoke "com.sun.tools.javac.code.Type.baseType()" because "tree.init.type" is null
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitVarDef(Attr.java:1317)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCVariableDecl.accept(JCTree.java:1027)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:677)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:751)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStats(Attr.java:770)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitBlock(Attr.java:1448)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:1091)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:677)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:751)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitMethodDef(Attr.java:1238)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:921)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:677)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:751)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClassBody(Attr.java:5478)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClass(Attr.java:5369)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClass(Attr.java:5200)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attrib(Attr.java:5145)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1317)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1290)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.analyze(JavacTaskImpl.java:404)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.lambda$analyze$1(JavacTaskImpl.java:379)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.invocationHelper(JavacTaskImpl.java:152)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.analyze(JavacTaskImpl.java:379)
        ... 28 more

---------- BEGIN SOURCE ----------
var a = a;
---------- END SOURCE ----------

FREQUENCY : always