sudo dnf install qpdf-devel python3.11 -m venv env cd env source ./bin/activate python -m pip install IPython python -m pip install sphinx sphinx_issues sphinx_design sphinx_rtd_theme git clone https://github.com/pikepdf/pikepdf cd pikepdf/ python -m pip install . cd docs/ ~/env/bin/sphinx-build . ../html 

(gdb) py-bt Traceback (most recent call first): File "/home/vstinner/env/lib/python3.11/site-packages/pikepdf/_methods.py", line 798, in open pdf._tmp_stream = tmp_stream File "<ipython-input-5-851f84133ed8>", line 1, in <cell line: 0> File "/home/vstinner/env/lib/python3.11/site-packages/IPython/core/interactiveshell.py", line 3398, in run_code exec(code_obj, self.user_global_ns, self.user_ns) File "/home/vstinner/env/lib/python3.11/site-packages/IPython/core/interactiveshell.py", line 3338, in run_ast_nodes if await self.run_code(code, result, async_=asy): (...) (gdb) where #0 0x00000000004a5af3 in _PyDictKeys_StringLookup (dk=0x0, key='_tmp_stream') at Objects/dictobject.c:1011 #1 0x00000000005805c1 in specialize_dict_access (owner=owner@entry=<pikepdf._qpdf.Pdf at remote 0x7fffdf2f35f0>, instr=instr@entry=0x1289664, type=type@entry=0x11afa20, name=name@entry='_tmp_stream', values_op=values_op@entry=154, hint_op=hint_op@entry=159, base_op=95, kind=<optimized out>) at Python/specialize.c:625 #2 0x0000000000580a42 in _Py_Specialize_StoreAttr (owner=<pikepdf._qpdf.Pdf at remote 0x7fffdf2f35f0>, instr=0x1289664, name='_tmp_stream') at Python/specialize.c:813 #3 0x000000000041fbe7 in _PyEval_EvalFrameDefault (tstate=0x84d910 <_PyRuntime+166320>, frame=0x7ffff7fb51d0, throwflag=18545184) at Python/ceval.c:3597 #4 0x000000000053dc20 in _PyEval_EvalFrame (throwflag=0, frame=0x7ffff7fb5170, tstate=0x84d910 <_PyRuntime+166320>) at ./Include/internal/pycore_ceval.h:73 (...) 

(gdb) frame 0 #0 0x00000000004a5af3 in _PyDictKeys_StringLookup (dk=0x0, key='_tmp_stream') at Objects/dictobject.c:1011 1011 if (!PyUnicode_CheckExact(key) || kind == DICT_KEYS_GENERAL) { (gdb) l 1006 */ 1007	Py_ssize_t 1008	_PyDictKeys_StringLookup(PyDictKeysObject* dk, PyObject *key) 1009	{ 1010 DictKeysKind kind = dk->dk_kind; 1011 if (!PyUnicode_CheckExact(key) || kind == DICT_KEYS_GENERAL) { 1012 return DKIX_ERROR; 1013 } 1014 Py_hash_t hash = unicode_get_hash(key); 1015 if (hash == -1) { (gdb) p dk $10 = (PyDictKeysObject *) 0x0 

(gdb) frame 1 #1 0x00000000005805c1 in specialize_dict_access (owner=owner@entry=<pikepdf._qpdf.Pdf at remote 0x7fffdf2f35f0>, instr=instr@entry=0x1289664, type=type@entry=0x11afa20, name=name@entry='_tmp_stream', values_op=values_op@entry=154, hint_op=hint_op@entry=159, base_op=95, kind=<optimized out>) at Python/specialize.c:625 (...) 622 // Virtual dictionary 623 PyDictKeysObject *keys = ((PyHeapTypeObject *)type)->ht_cached_keys; 624 assert(PyUnicode_CheckExact(name)); 625 Py_ssize_t index = _PyDictKeys_StringLookup(keys, name); (...) (gdb) p type->tp_name $7 = 0x11af850 "pikepdf._qpdf.Pdf" (gdb) p type->tp_base->tp_name $8 = 0x7fffe8614595 "pybind11_object" (gdb) p ((PyHeapTypeObject *)type)->ht_cached_keys $9 = (struct _dictkeysobject *) 0x0