Re: Glibc commit causing regression in gdb

[Florian Weimer <fweimer@redhat.com>]

* Emil Velikov via Libc-alpha:

> We have recently received a regression report in Arch Linux, where gdb
> attach fails with some applications.
> In particular, the issue originates in glibc 2.33, while gdb used is
> 10.1 and is 100% reproducible (here) with steam and gimp.
>
> Note that explicitly rebuilding gdb explicitly against the glibc does not help.
>
> After some digging I found the offending glibc commit
> 1daccf403b1bd86370eb94edca794dc106d02039 ("nptl: Move stack list
> variables into _rtld_global"). With the said commit the
> td_ta_map_lwp2thr() call in GDB fails, resulting in the infamous
>
> Error while reading shared library symbols for /usr/lib/libpthread.so.0:
> Cannot find user-level thread for LWP 2999060: generic error

> Can anyone confirm if the issue is reproducible with other distros?

There's a separate thread about this on the gdb-patches list, under the
slightly misleading subject of “GDB 10.2 Release -- 2021-04-11 update”:

  <https://sourceware.org/pipermail/gdb-patches/2021-April/thread.html>

I believe there was an earlier discussion as well, but I can't find it
right now.

Thanks,
Florian