Re: frequent hangs running ldd

[Mark Geisert <mark@maxrnd.com>]

On 5/24/2024 3:26 PM, Jeremy Drake via Cygwin wrote:
> On Sat, 25 May 2024, Takashi Yano wrote:
> 
>> On Fri, 24 May 2024 14:46:40 -0700 (PDT)
>> Jeremy Drake wrote:
>>>> Thanks for the report. However, I cannot reproduce the issue.
>>>> If it always hangs in GetConsoleProcessList (), I doubt it is not a cygwin
>>>> bug but a windows bug.
>>>>
>>>> By any chance, is the number of processes that attach to the same pty more
>>>> than 32768 in your environment?
>>>>
>>>
>>> I doubt it, I was running a shell with this command:
>>> find /usr/bin -name \*.dll -printf '%p:\n' -exec ldd '{}' \;
>>
>> Thanks for the details. I could reproduce the issue.
>> It seems that ldh.exe (which is called from ldd?) falls into infinite loop.
>> However, gdb cannot attach to ldh.exe...
>>
> 
> Windbg reports that ldh.exe is already being debugged.  I was able to do a
> "non-invasive" attach to ldh.exe in windbg, but it doesn't seem to be able
> to deal with the split debug symbols (gnulink?).  I don't know if gdb can
> do a non-invasive attach like that (or open a minidump assuming one could
> be made from a non-invasize attach in windbg).

ldd is the debugger of ldh. I found that Sysinternals Process Explorer 
can attach to ldh, show the threads, and can get stack backtraces which 
are refreshable. You have to convert addresses shown there into 
source-relevant addresses manually.

I'm bowing out for now as I think Takashi has a handle on this.
Cheers,

..mark