Re: EXC_BAD_ACCESS [was: persistent listeners]

[Ben Abbott]

On Mar 12, 2011, at 3:10 AM, logari81 wrote:

> On Thu, 2011-03-10 at 21:20 +0000, bpabbott wrote:
>> On Mar 10, 2011, at 02:34 PM, Konstantinos Poulios
>> <address@hidden> wrote:
>> 
>>> On Wed, Mar 9, 2011 at 12:16 PM, Konstantinos Poulios
>>> <address@hidden> wrote:
>>>> In the new implementation of subplot we have the problem that the
>>>> listeners that we use for the synchronization of subplots are
>>> deleted
>>>> once something is plotted on a subplot.
>>>> 
>>>> The attached patches implement persistent listeners, i.e.:
>>>> 
>>>> 1. listeners added with:
>>>> addlistener (handle, propertyname, cbfunction, "persistent")
>>>> will not be removed by the c++ method "remove_all_listeners", nor
>>> by a
>>>> call to delete_listener() with empty arguments list.
>>>> 
>>>> 2. however, explicitly removing a persistent listener from the
>>> frontend with:
>>>> dellistener (handle, propertyname, cbfunction)
>>>> should still work.
>>>> 
>>>> Please take a look at the patches so that I can push them if it is
>>> ok,
>>>> so that we can make some progress with the subplot fixes.
>>>> 
>>>> Kostas
>>> 
>>> I have just pushed a modified/fixed version of these patches.
>>> Actually
>>> with a bit modified policy than the one described in my previous
>>> mail:
>>> 
>>> 1. One can add a persistent listener with
>>> addlistener (handle, propertyname, cbfunction, "persistent")
>>> 
>>> 2 One can delete all persistent listeners on a property with
>>> dellistener (handle, propertyname, "persistent")
>>> 
>>> This change will allow us to fix the known issues with subplot.
>>> 
>>> Regards
>>> 
>>> Kostas
>> 
>> With this in place, Octave crashes for me when I try to create a plot
>> with fltk active.
>> 
>> 
>> octave:1> graphics_toolkit fltk
>> 
>> Reading symbols for shared libraries . done
>> 
>> Reading symbols for shared libraries . done
>> 
>> octave:2> plot (1:10)
>> 
>> Reading symbols for shared libraries . done
>> 
>> 
>> Program received signal EXC_BAD_ACCESS, Could not access memory.
>> 
>> Reason: KERN_PROTECTION_FAILURE at address: 0x00000000
>> 
>> 0x927d725e in glMatrixMode ()
>> 
>> (gdb) bt
>> 
>> #0  0x927d725e in glMatrixMode ()
>> 
>> #1  0x03705dbe in OpenGL_fltk::setup_viewport ()
>> at 
>> /Users/bpabbott/Development/mercurial/octave/src/DLD-FUNCTIONS/__init_fltk__.cc:146
>> 
>> #2  0x03705dbe in OpenGL_fltk::resize (this=0x3609a50, xx=0, yy=20,
>> ww=640, hh=440) at DLD-FUNCTIONS/__init_fltk__.cc:129
>> 
>> #3  0x037155d6 in fltk_uimenu::show ()
>> at 
>> /Users/bpabbott/Development/mercurial/octave/src/DLD-FUNCTIONS/__init_fltk__.cc:788
>> 
>> #4  0x037155d6 in plot_window::show_menubar ()
>> at 
>> /Users/bpabbott/Development/mercurial/octave/src/DLD-FUNCTIONS/__init_fltk__.cc:789
>> 
>> #5  0x037155d6 in plot_window::plot_window (this=0x36094d0, xx=0,
>> yy=0, ww=640, hh=480, address@hidden) at
>> DLD-FUNCTIONS/__init_fltk__.cc:737
>> 
>> #6  0x03715caa in plot_window [inlined] ()
>> at 
>> /Users/bpabbott/Development/mercurial/octave/src/DLD-FUNCTIONS/__init_fltk__.cc:755
>> 
>> #7  0x03715caa in figure_manager::do_new_window (this=0x33b8870,
>> address@hidden) at DLD-FUNCTIONS/__init_fltk__.cc:1572
>> 
>> #8  0x037042bb in figure_manager::new_window ()
>> at 
>> /Users/bpabbott/Development/mercurial/octave/src/DLD-FUNCTIONS/__init_fltk__.cc:1450
>> 
>> #9  0x037042bb in __fltk_redraw__ () at
>> DLD-FUNCTIONS/__init_fltk__.cc:1767
>> 
>> #10 0x03715f77 in fltk_graphics_toolkit::redraw_figure
>> (this=0x3606c40, address@hidden) at
>> DLD-FUNCTIONS/__init_fltk__.cc:1865
>> 
>> #11 0x001fdef4 in graphics_toolkit::redraw_figure ()
>> at /Users/bpabbott/Development/mercurial/octave/src/graphics.h:7618
>> 
>> #12 0x001fdef4 in Fdrawnow (address@hidden) at graphics.cc:7618
>> 
>> #13 0x00498fad in octave_builtin::do_multi_index_op (this=0x3864140,
>> nargout=0, address@hidden, lvalue_list=0x0) at ov-builtin.cc:128
>> 
>> #14 0x00499377 in octave_builtin::do_multi_index_op (this=0x3864140,
>> nargout=0, address@hidden) at ov-builtin.cc:98
>> 
>> #15 0x0007e578 in octave_value::do_multi_index_op (this=0xbfffb518,
>> nargout=0, address@hidden) at ov.cc:1266
>> 
>> #16 0x0005d5f1 in feval (address@hidden, address@hidden,
>> nargout=0) at oct-parse.yy:4140
>> 
>> #17 0x0003af99 in interactive_input (address@hidden,
>> force_readline=false) at input.cc:237
>> 
>> #18 0x0003ba25 in std::string::operator= () at /usr/include/c
>> ++/4.2.1/bits/basic_string.h:280
>> 
>> #19 0x0003ba25 in octave_gets [inlined] ()
>> at /Users/bpabbott/Development/mercurial/octave/src/input.cc:280
>> 
>> #20 get_user_input [inlined] ()
>> at /Users/bpabbott/Development/mercurial/octave/src/input.cc:351
>> 
>> #21 0x0003ba25 in octave_read (buf=0x3a50600 "", max_size=8192) at
>> input.cc:373
>> 
>> #22 0x0003ccd3 in yy_get_next_buffer () at lex.cc:3097
>> 
>> #23 0x0004df11 in octave_lex () at lex.cc:2939
>> 
>> #24 0x00063a9d in octave_parse () at oct-parse.cc:2395
>> 
>> #25 0x0041a5c9 in main_loop () at toplev.cc:567
>> 
>> #26 0x003b591d in octave_main (argc=6, argv=0xbfffc354, embedded=0) at
>> octave.cc:935
>> 
>> #27 0x00001f80 in main (argc=6, argv=0xbfffc354) at main.c:35
>> 
>> 
>> Occasionally, I see some strange results on MacOS. Can someone else
>> confirm this behavior?
>> 
>> Ben
> 
> Hmm, this is very strange because normal plotting shouldn't involve any
> listeners at all, should it? I couldn't reproduce this issue on two
> different computers but I cannot try it on a Mac.
> 
> Have you tried rebuilding everything from scratch?
> 
> Kostas

I don't see this on Ubuntu, but am able to reproduce in on two Macs. The root 
of the problem may be due to fltk-aqua-1.1.10 , the older gcc 4.2.1 I'm using, 
or Apple's patches to gcc. 

Ben