threads/1871: Cannot access threads at all in x86_64-linux

[jkohen at users dot sourceforge dot net]

>Number:         1871
>Category:       threads
>Synopsis:       Cannot access threads at all in x86_64-linux
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Feb 17 23:38:01 UTC 2005
>Closed-Date:
>Last-Modified:
>Originator:     jkohen@users.sourceforge.net
>Release:        GNU gdb 6.3-debian
>Organization:
>Environment:
Linux 2.6.10-ck5/x86_64, 64-bit kernel compiled with gcc-3.4.x and with pure 64-bit userland compiled with gcc-3.4.x and gcc-4.0-preX.
Glibc 2.3.2.
It's a current Debian-AMD64/gcc-3.4 distribution.
>Description:
GDB cannot show me thread information or set breakpoints on threads beyond #0. See the attached test program and gdb log.

The program runs fine from inside GDB and from the shell.
>How-To-Repeat:
The GCC used to compile the program is gcc (GCC) 3.4.4 20050203 (prerelease) (Debian 3.4.3-9.0.0.1.gcc4) with the following command line:
gcc -lpthread -ggdb -Wall -ofoo foo.c

and the following produces the same results:
gcc -O0 -lpthread -ggdb -Wall -ofoo foo.c

Note that "info threads" gives an empty list even if issued before the thread returns.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="foo.c"

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