Re: crashes when exiting octave and loading swig-wrapped code

[John W. Eaton]

On  3-Nov-2009, Jaroslav Hajek wrote:

| On Sat, Oct 24, 2009 at 3:05 AM, John W. Eaton <address@hidden> wrote:
| > On 21-Oct-2009, Soeren Sonnenburg wrote:
| >
| > | I am seeing crashes when exiting octave when I use swig-wrapped code but
| > | only when loading multiple modules (with potentially overlapping
| > | variables/functions).
| > |
| > | Well it seems to be some invalid delete/free occurring only when closing
| > | octave (gdb & valgrind outputs follow):
| > |
| > | (this happens when just *loading* multiple modules of the shogun toolbox
| > | (http://www.shogun-toolbox.org)):
| > |
| 
| > Yes, it's a known problem that you can't load a .oct file that creates
| > a variable (or is it just a user-defined class?) then clear the .oct
| > file and expect to continue to use the variables that were created.
| > I think you can avoid the problem by locking the .oct file that
| > creates the object.
| >
| > We've had some discussions about making Octave delay unloading the
| > file until all objects created by it are deleted.  That might be
| > better, but so far no one has done the work.
| >
| > jwe
| 
| I inspected the code a bit, and the basic obstacle I see is the
| octave_shlib::close method, which runs a hook function for each
| registered function, and then forces dlclose() (or equivalent), even
| though there may still be references to the shlib object.
| 
| John, can you give me a clue why this is so?

Let's move this discussion to the maintainers list.

jwe