gdb: "Can't fetch registers from thread 4: No such thread"

[Thomas Schwinge]

Hello!

Several people have seen gdb failing printing only messages like
#v+
Can't fetch registers from thread 4: No such thread
#v+
or
#v+
Can't fetch registers from thread 2: No such thread
#v-

I've found the reason for these failures (at least on my system).
I did not have $SHELL set to /bin/sh, but to a shell script that would
finally exec into /bin/sh.

#v+
$ cat > tmpshell <<"EOF"
#!/bin/sh
exec /bin/sh "$@"
EOF
$ chmod +x tmpshell
$ echo run | env SHELL=`pwd`/tmpshell gdb /bin/true
GNU gdb 6.3-debian
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386-gnu"...(no debugging symbols found)

(gdb) Starting program: /bin/true 
Can't fetch registers from thread 2: No such thread
Can't fetch registers from thread 2: No such thread
(gdb)
#v-

#v+
$ echo run | env SHELL=/bin/sh gdb /bin/true
GNU gdb 6.3-debian
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386-gnu"...(no debugging symbols found)

(gdb) Starting program: /bin/true 
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)

Program exited normally.
(gdb)
#v-

This tests were done on a 'arp-get upgrade'd Debian GNU/Hurd K8 system.


If nobody of you has a clue about that issue (apart from just using
'SHELL=/bin/sh gdb ...' ;-), I'll report it to a gdb mailing list (or to
Debian BTS?).


Regards,
 Thomas