On Thu, 14 May 2026 07:08:02 GMT, Yasumasa Suenaga <[email protected]> wrote:

>> serviceability/sa/TestJhsdbJstackMixedWithXComp.java failure on CentOS 7 was 
>> reported.
>> 
>> That error is caused that glibc on CentOS 7 has Personality Routine and LSDA 
>> (language-specific data area). SA does not support them, and skip them so 
>> far. Thus DWARF parser could not continue to unwind call stacks.
>> 
>> Personality Routine and LSDA are for exception handling for the language 
>> which supports exception like C++ (See [LLVM 
>> document](https://llvm.org/docs/ExceptionHandling.html) for details). They 
>> are not needed for stack unwinding in debugger like SA, but we need to skip 
>> DWARF augmentation correctly.
>> 
>> This change has passed serviceability/sa tests on both CentOS 7 and Fedora 
>> 44.
>> 
>> ---------
>> - [x] I confirm that I make this contribution in accordance with the 
>> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai).
>
> Yasumasa Suenaga has updated the pull request incrementally with one 
> additional commit since the last revision:
> 
>   Return null if DWARF is missing

Looks like my printing of the stack trace to System.out is not reliable. Pstack 
has its owne PrintStream, and I was seeing the stack trace turning up in 
various parts of the output when I used System.out. Now I have it printing to 
the Pstack PrintStream, and I'm seeing the exception printing after the 
following thread:

0x00007f622ef2f38a      __futex_abstimed_wait_common + 0xca
0x00007f622ef33e34      __pthread_clockjoin_ex + 0x144
0x00007f622f0c3cd6      CallJavaMainInNewThread + 0xa6
0x00007f622f0c0dae      ContinueInNewThread + 0x6e
0x00007f622f0c1afc      JLI_Launch + 0xb4c
0x0000560848ca7ad4      main + 0x134
0x00007f622eed1610      __libc_start_call_main + 0x80
0x00007f622eed16c0      __libc_start_main_alias_2 + 0x80

I used gdb on the core file to produce a stack trace, and it actually stops at 
main, so SA is doing better than gdb, but maybe it is going too far and falling 
off the end (start).

-------------

PR Comment: https://git.openjdk.org/jdk/pull/31085#issuecomment-4452253308

Reply via email to