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From: Simon Marchi <simon.marchi@polymtl.ca>
To: Florian Weimer <fweimer@redhat.com>, libc-alpha@sourceware.org
Subject: Re: [PATCH] nptl: Move stack list variables into _rtld_global
Date: Fri, 5 Mar 2021 11:54:23 -0500	[thread overview]
Message-ID: <0f7bf7d7-36f9-ce7f-0390-4b39eeb0fffc@polymtl.ca> (raw)
In-Reply-To: <87a6vlthqn.fsf@oldenburg2.str.redhat.com>



On 2020-11-13 10:10 a.m., Florian Weimer wrote:
> Now __thread_gscope_wait (the function behind THREAD_GSCOPE_WAIT,
> formerly __wait_lookup_done) can be implemented directly in ld.so,
> eliminating the unprotected GL (dl_wait_lookup_done) function
> pointer.

Hi Florian,

Presumably starting with this commit (I don't really know how to build a
glibc and test against it), GDB fails to attach to a threaded process
because libthread_db fails to initialize.  See:

  https://sourceware.org/bugzilla/show_bug.cgi?id=27526

The difference in behavior as seen from GDB is that libthread_db now
asks to look up a symbol "_dl_stack_user" in module NULL.  GDB can't
find this symbol, which fails the initialization.

Can you shed some light on this?  Is this request expected, and where is
GDB expected to find this symbol?

Thanks,

Simon


  parent reply	other threads:[~2021-03-05 16:54 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-13 15:10 Florian Weimer
2020-11-16 18:02 ` Adhemerval Zanella
2021-03-05 16:54 ` Simon Marchi [this message]
2021-03-05 17:15   ` Florian Weimer
2021-03-05 17:26     ` Andreas Schwab
2021-03-05 17:58     ` Simon Marchi
2021-03-05 18:03       ` Florian Weimer
2021-03-05 18:45         ` Simon Marchi
2021-03-05 19:00           ` Florian Weimer
2021-03-29  8:26             ` Florian Weimer
2021-03-29 14:29               ` Simon Marchi

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