Inconsistent behavior when trying to probe return values from multiple methods

[jbachorik]

Following snippet leads to NPE

@OnMethod(clazz="extra.HelloWorld", method="/.*/", location = @Location(Kind.RETURN))
    public static void trace(@ProbeMethodName(fqn = true) String pmn, @Return String o) {

java.lang.NullPointerException
at java.lang.String.(String.java:198)
at com.sun.btrace.org.objectweb.asm.Type.getInternalName(Unknown Source)
at com.sun.btrace.util.LocalVariableHelperImpl.storeNewLocal(LocalVariableHelperImpl.java:291)
at com.sun.btrace.util.templates.TemplateExpanderVisitor.storeNewLocal(TemplateExpanderVisitor.java:64)
at com.sun.btrace.runtime.MethodInstrumentor.storeNewLocal(MethodInstrumentor.java:298)
at com.sun.btrace.runtime.Instrumentor$15.callAction(Instrumentor.java:1232)
at com.sun.btrace.runtime.Instrumentor$15.onMethodReturn(Instrumentor.java:1275)
at com.sun.btrace.runtime.MethodReturnInstrumentor.visitInsn(MethodReturnInstrumentor.java:62)
at com.sun.btrace.org.objectweb.asm.MethodVisitor.visitInsn(Unknown Source)
at com.sun.btrace.org.objectweb.asm.ClassReader.a(Unknown Source)
at com.sun.btrace.org.objectweb.asm.ClassReader.b(Unknown Source)
at com.sun.btrace.org.objectweb.asm.ClassReader.accept(Unknown Source)
at com.sun.btrace.org.objectweb.asm.ClassReader.accept(Unknown Source)
at com.sun.btrace.runtime.InstrumentUtils.accept(InstrumentUtils.java:119)
at com.sun.btrace.runtime.InstrumentUtils.accept(InstrumentUtils.java:115)
at com.sun.btrace.agent.Client.instrument(Client.java:395)
at com.sun.btrace.agent.Client.doTransform(Client.java:215)
at com.sun.btrace.agent.Client.transform(Client.java:167)
at sun.instrument.TransformerManager.transform(TransformerManager.java:188)
at sun.instrument.InstrumentationImpl.transform(InstrumentationImpl.java:428)
at sun.instrument.InstrumentationImpl.retransformClasses0(Native Method)
at sun.instrument.InstrumentationImpl.retransformClasses(InstrumentationImpl.java:144)
at com.sun.btrace.agent.Main$4.run(Main.java:484)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)

With

@OnMethod(clazz="extra.HelloWorld", location = @Location(Kind.RETURN))
    public static void trace(@ProbeMethodName(fqn = true) String pmn, @Return String o) {

we don't get NPE but the methods are not matched.