Package: gdb
Version: 7.12-6
Severity: normal
Tags: upstream
Attempting to read thread-local variables (e.g. errno) from the
Python interface fails with "Cannot find thread-local storage", but
reading the same variable from the (gdb) prompt works. Transcript:
$ cat test.c
#include <stdio.h>
#include <errno.h>
int main(void)
{
printf("%d\n", errno);
}
$ gcc -g test.c
$ gdb ./a.out
GNU gdb (Debian 7.12-6) 7.12.0.20161007-git
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from ./a.out...done.
(gdb) b main
Breakpoint 1 at 0x704: file test.c, line 6.
(gdb) r
Starting program: /home/zack/a.out
Breakpoint 1, main () at test.c:6
6 printf("%d\n", errno);
(gdb) p errno
$1 = 0
(gdb) pi
>>> gdb.parse_and_eval('errno')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
gdb.error: Cannot find thread-local storage for process 8486, shared library
/lib/x86_64-linux-gnu/libc.so.6:
Cannot find thread-local variables on this target
I observe the same behavior with 7.12-6 (unstable) and 8.0-1 (experimental).
-- System Information:
Debian Release: 9.0
APT prefers unstable
APT policy: (501, 'unstable'), (500, 'unstable-debug'), (500,
'testing-debug'), (500, 'testing'), (101, 'experimental'), (1,
'experimental-debug')
Architecture: amd64 (x86_64)
Foreign Architectures: i386
Kernel: Linux 4.9.0-3-amd64 (SMP w/8 CPU cores)
Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8),
LANGUAGE=en_US.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
Versions of packages gdb depends on:
ii libbabeltrace-ctf1 1.5.2-1
ii libbabeltrace1 1.5.2-1
ii libc6 2.24-12
ii libexpat1 2.2.1-1
ii liblzma5 5.2.2-1.2+b1
ii libncurses5 6.0+20161126-1
ii libpython3.5 3.5.3-3
ii libreadline7 7.0-3
ii libtinfo5 6.0+20161126-1
ii zlib1g 1:1.2.8.dfsg-5
Versions of packages gdb recommends:
ii libc6-dbg [libc-dbg] 2.24-12
Versions of packages gdb suggests:
pn gdb-doc <none>
ii gdbserver 7.12-6
-- no debconf information
