[aarch64-port-dev ] RFR: 8209413: AArch64: NPE in clhsdb jstack command

[Andrew Haley]

On 2/1/19 9:22 AM, Nick Gasson (Arm Technology China) wrote:
> On AArch64, if you use "jhsdb clhsdb --pid=..." to attach a debugger to 
> a Java process, and then run "jstack -v" while any thread is executing a 
> native method, you will get a NullPointerException like this:

This does not happen for me. I have a test case which runs a native
method; the native method does not return. I then run jstack -v and
get a clean stack trace, regardless of whether it's interpreted or
compiled:

"main" #1 prio=5 tid=0x0000ffff7001a000 nid=0x596c runnable [0x0000ffff7624e000]
   java.lang.Thread.State: RUNNABLE
   JavaThread state: _thread_in_native
 - Spinner.main(java.lang.String[]) @bci=0, line=9, pc=0x0000ffff6d6954d8, Method*=0x0000ffff2321e380 (Compiled frame; information may be imprecise)

Locked ownable synchronizers:
    - None

I tried various combinations of Xcomp and tiered compilation, release
and debug builds. What did you do?

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
EAC8 43EB D3EF DB98 CC77 2FAD A5CD 6035 332F A671

-------------- next part --------------
A non-text attachment was scrubbed...
Name: Spinner.c
Type: text/x-csrc
Size: 213 bytes
Desc: not available
URL: <https://mail.openjdk.java.net/pipermail/serviceability-dev/attachments/20190205/bc2a2c3a/Spinner.c>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Spinner.h
Type: text/x-chdr
Size: 358 bytes
Desc: not available
URL: <https://mail.openjdk.java.net/pipermail/serviceability-dev/attachments/20190205/bc2a2c3a/Spinner.h>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Spinner.java
Type: text/x-java
Size: 182 bytes
Desc: not available
URL: <https://mail.openjdk.java.net/pipermail/serviceability-dev/attachments/20190205/bc2a2c3a/Spinner.java>