On 2008-06-06 12:31, Laurent Gautier wrote:

Dear List,

I am having trouble with some of the use-cases for a C-written module of my own (if curious, I am working on Python-R interface... this is open source so I can provide the whole source if needed).

Everything is working just fine and as expected... until the python process exits.

When running my test script through gdb and with the '-v' flag for Python, it ends with

# cleanup __main__

Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 0xb7dde8c0 (LWP 19670)] 0x080f3d08 in PyObject_GC_UnTrack ()

---

I have looked for information on the internet... but have not found much. Would this kind of error be familiar to anyone ?

I've never seen this particular error before, but it's likely that you have a ref count bug somewhere in your code.

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I have probably found the problem. I report it here in case someone has the same issue later.

In my tp_new I had:

PyObject_New(MyType, type);

(and it was working just fine until I started with subclasses)

while it seems that it should have been:

type->tp_alloc(type, 0);

L.

2008/6/6 Laurent Gautier lgautier@gmail.com:

Dear List,

I am having trouble with some of the use-cases for a C-written module of my own (if curious, I am working on Python-R interface... this is open source so I can provide the whole source if needed).

Everything is working just fine and as expected... until the python process exits.

When running my test script through gdb and with the '-v' flag for Python, it ends with

# cleanup __main__

Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 0xb7dde8c0 (LWP 19670)] 0x080f3d08 in PyObject_GC_UnTrack ()

---

I have looked for information on the internet... but have not found much. Would this kind of error be familiar to anyone ?

Thanks,

Laurent

I stumbled upon some documentation about that (it had to do with circular references, AFAIR)... and I don't think that I have that flag set. I only have: Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE

2008/6/7 Adam Olsen rhamph@gmail.com:

On Fri, Jun 6, 2008 at 1:40 PM, Laurent Gautier lgautier@gmail.com wrote:

...

I have probably found the problem. I report it here in case someone has the same issue later.

In my tp_new I had:

PyObject_New(MyType, type);

(and it was working just fine until I started with subclasses)

while it seems that it should have been:

type->tp_alloc(type, 0);

Do you have Py_TPFLAGS_HAVE_GC set? That'd require you to use PyObject_GC_New, which'd allocate extra space for the tracking flag, and the absence of which would explain the crash.

-- Adam Olsen, aka Rhamphoryncus