[PyQt] Py_XDECREF(*sipUnused) Segfault

[Matteo Bertozzi]

I've a segfault for a NULL pointer access:
    Py_XDECREF(*sipUnused);

The code to reproduce segfault is really simple:
Method code set sipIsError to True and raise PyExc_ValueError.

____(sipSimpleWrapper *, PyObject *sipArgs, PyObject *sipKwds, PyObject
**sipUnused, PyObject **, PyObject **sipParseErr)

sipUnused seems to be NULL, and Py_XDECREF(*sipUnused)
try to access to address 0... and the result is a segfault.

A very simple workaround can be check sipUnused before call Py_XDECREF.

> --- sip/sipgen/gencode.c	(revision 29039)
> +++ sip/sipgen/gencode.c	(working copy)
> @@ -10294,7 +10294,7 @@
>  
>          prcode(fp,
>  "\n"
> -"            Py_XDECREF(*sipUnused);\n"
> +"            if (sipUnused != NULL) Py_XDECREF(*sipUnused);\n"
>  "            sipAddException(sipError, sipParseErr);\n"
>  "\n"
>  "            if (sipError == sipErrorFail)\n"
> @@ -10308,7 +10308,7 @@
>              prcode(fp,
>  "            if (sipIsErr)\n"
>  "            {\n"
> -"                Py_XDECREF(*sipUnused);\n"
> +"                if (sipUnused != NULL) Py_XDECREF(*sipUnused);\n"
>  "                sipAddException(sipErrorFail, sipParseErr);\n"
>  "                return NULL;\n"
>  "            }\n"

Thanks.

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