Brian pointed out to me that this change missed to add the annotation to bridge methods. Here is an updated version that takes those into account. I also needed to update the test to verify that bridge methods were correctly annotated - it got a little bit more complex since I had to force bridges being used.
new webrev: http://cr.openjdk.java.net/~sla/8025636/webrev.01/ <http://cr.openjdk.java.net/~sla/8025636/webrev.01/> Thanks, /Staffan > On 3 feb 2015, at 10:15, Staffan Larsen <staffan.lar...@oracle.com> wrote: > > Hi, > > Please review this patch for hiding the lambda proxy frame in stack traces: > > bug: https://bugs.openjdk.java.net/browse/JDK-8025636 > <https://bugs.openjdk.java.net/browse/JDK-8025636> > webrev: http://cr.openjdk.java.net/~sla/8025636/webrev.00/ > <http://cr.openjdk.java.net/~sla/8025636/webrev.00/> > > This is a straightforward addition of the LambdaForm$Hidden annotation to the > generated methods. What is surprising is that this works even if > LambdaForm$Hidden is a package-private class in java.lang.invoke and thus not > accessible from most of the generated classes. There is some discussion of > and answers to this in the bug, but essentially this works because the > annotation class is never resolved and the code in Hotspot that looks for the > annotation amounts to nothing more than string comparisons. > > Hidden stack frames can be shown by running with > “-XX:+UnlockDiagnosticVMOptions -XX:+ShowHiddenFrames”. > > For an example of what this patch does, consider this code: > > Runnable r = () -> { throw new RuntimeException(); }; > r.run(); > > Previously, this would output: > > java.lang.RuntimeException > at pkg.Foo.lambda$main$0(Foo.java:5) > at pkg.Foo$$Lambda$1/2001112025.run(<Unknown>:1000000) > at pkg.Foo.main(Foo.java:15) > > With the patch it looks like this: > > java.lang.RuntimeException > at pkg.Foo.lambda$main$0(Foo.java:5) > at pkg.Foo.main(Foo.java:15) > > > Thanks, > /Staffan >
