Do we need to pyincref here?

[colinfang]

I am investigating a Segmentation Fault possibly because of py_decref issue.

--> Start pydecref: ps=PyObject NULL"
"Start pydecref 140082311589056: js=jL_Function_call|kw_"

signal (11): Segmentation fault

The line kw = PyDict{Symbol,PyAny}(PyObject(kw_)) looks suspecious.
We borrowed a PyPtr, don't we need to pyincref it?

It also aplies to line args = PyObject(args_)

function jl_Function_call(self_::PyPtr, args_::PyPtr, kw_::PyPtr)
    ret_ = convert(PyPtr, C_NULL)
    args = PyObject(args_)
    try
        f = unsafe_pyjlwrap_to_objref(self_)::Function
        if kw_ == C_NULL
            ret = PyObject(f(convert(PyAny, args)...))
        else
            kw = PyDict{Symbol,PyAny}(PyObject(kw_))
            kwargs = [ (k,v) for (k,v) in kw ]
            ret = PyObject(f(convert(PyAny, args)...; kwargs...))
        end
        ret_ = ret.o
        ret.o = convert(PyPtr, C_NULL) # don't decref
    catch e
        pyraise(e)
    finally
        args.o = convert(PyPtr, C_NULL) # don't decref
    end
    return ret_::PyPtr
end

[stevengj]

Good catch. I think you're right. The Python API manual is unclear on this point because it doesn't document the case of tp_call or other callback functions specifically. However, looking at the source code of PyObject_Call clearly indicates that the parameters are "borrowed" references, i.e. we aren't supposed to decref them.

[stevengj]

The args is actually safe because of the args.o = NULL in the finally clause. I just forgot to handle the kw case.