QT GUI sink: Seg faults in GR 3.7.2.1-149-g67aa043b

A flow graph that used to work in Gnuradio 3.7 now fails in 3.7.2.1

I’ve isolated it to the QT GUI Sink component, which causes the
flowgraph to immediately
aborts with a segmentation fault.

Core was generated by `python ./top_block.py’.
Program terminated with signal 11, Segmentation fault.
#0 0x00007fc7f6c01125 in ?? ()
(gdb) i stack
#0 0x00007fc7f6c01125 in ?? ()
#1 0x00007fc7eeca32e9 in ?? ()
#2 0x0000000000000000 in ?? ()
(gdb)

Sorry - don’t have symbol generation enabled…

If that QT GUI Sink is replaced by QT GUI Frequency Sink then everything
runs OK.

Is this a known issue, or has the QT GUI Sink been deprecated? It
appears on the lis
of choosable blocks in Gnuradio Companion.

I did not find an issue in the issue tracker related to this specific
block.

– Tom, N5EG

On Wed, Feb 5, 2014 at 2:25 AM, Tom McDermott [email protected]
wrote:

#0 0x00007fc7f6c01125 in ?? ()
the lis
of choosable blocks in Gnuradio Companion.

I did not find an issue in the issue tracker related to this specific block.

– Tom, N5EG

Thanks for point this out. Can you open an Issue on gnuradio.org so
that we don’t forget this problem? I won’t have a chance to look at it
for a few days.

The qtgui sinks are not officially deprecated, yet, because we don’t
have a replacement for them. I’d like to make a replacement that
simply wraps the other stand-alone GUI blocks into a tabbed view with
a few control widgets on it so that we aren’t duplicating the
processing (which would also mean the new features like the
middle-click menu would be available in this mode, too). Once that’s
actually done, we’ll deprecate these sinks. Until then, we want to
work out issues like this.

Tom

On Wed, Feb 5, 2014 at 9:35 AM, Tom R. [email protected] wrote:

(gdb) i stack
Is this a known issue, or has the QT GUI Sink been deprecated? It appears on

The qtgui sinks are not officially deprecated, yet, because we don’t
have a replacement for them. I’d like to make a replacement that
simply wraps the other stand-alone GUI blocks into a tabbed view with
a few control widgets on it so that we aren’t duplicating the
processing (which would also mean the new features like the
middle-click menu would be available in this mode, too). Once that’s
actually done, we’ll deprecate these sinks. Until then, we want to
work out issues like this.

Tom

Let me clarify, I’m talking about the “QTGUI Sink” block specifically
for deprecation, not the qtgui concept or anything.

Tom