Segfault

GNU Radio
1

Hi to all.
This is my first post here…i hope to have choosen the right place to
ask…

I’m currently trying to compile gqrx and gnuradio…everything went
well,
but when i run gqrx it won’t start and give me this error:

gqrx[5865]: segfault at 12d0 ip 00007f570ee76d2f sp 00007fff60fd9000
error
4 in libgnuradio-pmt-3.7.6git.so.0.0.0[7f570ee44000+50000]

I’ve asked on the gqrx group and the author (hi csete!!!) told me that
most probably it’s a bug/problem on gnuradio.

I’ve no idea what’s wrong…

PS: it was running ok before i updated with git pull gnuradio (didn’t do
that since 2 months…).

PSS: Sorry for my english!!!

2

Hi Michele,

if you built GNU Radio/gqrx with gcc, then the GNU Debugger might be of
immensive help.
First make sure you’ve built GNU Radio with debugging symbols (“cmake
-DCMAKE_BUILD_TYPE=RelWithDebInfo […]”), then start gqrx in the
debugger:

?> gdb $(which gqrx)
[lots of text from gdb]
(gdb) run []

should start gqrx and run until it segfaults. then use the backtrace
command in gdb:

(gdb) bt []

which should show you in which function call hierarchy the fault
occurred.

Greetings,
Marcus

PS: don’t worry about your English, it’s quite fine :slight_smile:

3

Il Sun, 30 Nov 2014 21:16:12 +0100, Marcus Müller ha scritto:

(gdb) run []
Marcus

gqrx[5865]: segfault at 12d0 ip 00007f570ee76d2f sp 00007fff60fd9000

PSS: Sorry for my english!!!

Discuss-gnuradio mailing list [email protected]
Discuss-gnuradio Info Page

the project uses qmake instead of cmake…but i’ve tryed anyway…
i get this from dbg:

Starting program: /home/michele/Scrivania/gqrx.git/build/gqrx
[Thread debugging using libthread_db enabled]
Using host libthread_db library
“/lib/x86_64-linux-gnu/libthread_db.so.1”.

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff6001d2f in pmt::string_to_symbol(std::string const&) () from
/
usr/local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
(gdb) bt
#0 0x00007ffff6001d2f in pmt::string_to_symbol(std::string const&) ()
from /usr/local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
#1 0x00007ffff6002079 in pmt::intern(std::string const&) () from /usr/
local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
#2 0x00007fffee193a0d in ?? () from
/usr/lib/x86_64-linux-gnu/libgnuradio-
blocks.so.3.7.3
#3 0x00007ffff7dea13a in call_init (l=,
argc=argc@entry=1,
argv=argv@entry=0x7fffffffe078, env=env@entry=0x7fffffffe088) at dl-
init.c:78
#4 0x00007ffff7dea223 in call_init (env=,
argv=, argc=, l=) at dl-init.c:36
#5 _dl_init (main_map=0x7ffff7ffe1c8, argc=1, argv=0x7fffffffe078,
env=0x7fffffffe088) at dl-init.c:126
#6 0x00007ffff7ddb24a in _dl_start_user () from /lib64/ld-linux-
x86-64.so.2
#7 0x0000000000000001 in ?? ()
#8 0x00007fffffffe38c in ?? ()
#9 0x0000000000000000 in ?? ()

Is this what you meant?

4

Is this what you meant?
Exactly!

So let’s have a look at the backtrace:

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff6001d2f in pmt::string_to_symbol(std::string const&) () from
/
usr/local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
(gdb) bt
#0 0x00007ffff6001d2f in pmt::string_to_symbol(std::string const&) ()
from /usr/local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
#1 0x00007ffff6002079 in pmt::intern(std::string const&) () from /usr/
local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
#2 0x00007fffee193a0d in ?? () from
/usr/lib/x86_64-linux-gnu/libgnuradio-
blocks.so.3.7.3

There’s one problem I see here: libgnuradio-blocks has version 3.7.3 and
libgnuradio-pmt 3.7.6. This means you’re mixing versions!
It’s still a funny point to segfault, but you’ll have to make sure not
to mix 3.7.3 and 3.7.6. From the way things are named
(pmt-3.7.6git.so.0.0.0 vs blocks.so.3.7.3) I’d assume that you have one
installation of GNU Radio that you’ve built yourself, and one that you
installed via your distribution’s package manager, maybe?

Greetings,
Marcus

5

THANKS!!!
Yes…i did have 2 installations…removed the ones from package manager
did the trick!

6

Hi Michele - It looks like there are multiple GNU Radio installs being
caught in the execution: /usr/local/lib/ and /usr/lib/x86_64-linux-gnu/
:

{{{
Program received signal SIGSEGV, Segmentation fault.
0x00007ffff6001d2f in pmt::string_to_symbol(std::string const&) () from
/
usr/local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
(gdb) bt
#0 0x00007ffff6001d2f in pmt::string_to_symbol(std::string const&) ()
from /usr/local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
#1 0x00007ffff6002079 in pmt::intern(std::string const&) () from /usr/
local/lib/libgnuradio-pmt-3.7.6git.so.0.0.0
#2 0x00007fffee193a0d in ?? () from
/usr/lib/x86_64-linux-gnu/libgnuradio-
blocks.so.3.7.3
}}}

On Mac OS X this dual-linkage -could- cause issues depending on the
library linkage (flat or 2-level namespace; but, it likely would
anyway); I assume the same on Linux. I’d suggest limiting the number of
GR installs to just 1, and/or just making sure that any dependency is
linked to all of the correct GR libraries (those from the same install).

Good luck! - MLD