When they compile source code with -verbose option,
the following error messages are shown on the command line
and stop compiling.

./1.1/bin/javac -verbose A.java
[parsed A.java in 297 ms]
java.lang.NullPointerException
        at java.text.MessageFormat.format(MessageFormat.java)
        at java.text.MessageFormat.format(MessageFormat.java)
        at java.text.MessageFormat.format(MessageFormat.java)
        at sun.tools.javac.Main.getText(Main.java)
        at sun.tools.javac.BatchEnvironment.loadFile(BatchEnvironment.java)
        at sun.tools.javac.BatchEnvironment.loadDefinition(BatchEnvironment.java)
        at sun.tools.java.Environment.loadDefinition(Environment.java)
        at sun.tools.java.Environment.loadDefinition(Environment.java)
        at sun.tools.java.Environment.loadDefinition(Environment.java)
        at sun.tools.java.ClassDeclaration.getClassDefinition(ClassDeclaration.java)
        at sun.tools.javac.SourceClass.checkSupers(SourceClass.java)
        at sun.tools.javac.SourceClass.basicCheck(SourceClass.java)
        at sun.tools.java.ClassDeclaration.getClassDefinition(ClassDeclaration.java)
        at sun.tools.javac.Main.compile(Main.java)
        at sun.tools.javac.Main.main(Main.java)
error: An exception has occurred in the compiler; please file a bug report (###@###.###).
1 error
[done in 1295 ms]


***** source code of class A *****

public class A {

}

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