bpo-46347: Fix memory leak in PyEval_EvalCodeEx. (#30546)

First introduced in 0332e56

Author: 1st1

Misc/NEWS.d/next/Core and Builtins/2022-01-11-13-57-00.bpo-46347.Gd8M-S.rst

@@ -0,0 +1 @@
+Fix memory leak in PyEval_EvalCodeEx.

Python/ceval.c

@@ -6128,16 +6128,9 @@ PyEval_EvalCodeEx(PyObject *_co, PyObject *globals, PyObject *locals,
  }
  allargs = newargs;
  }
- PyObject **kwargs = PyMem_Malloc(sizeof(PyObject *)*kwcount);
- if (kwargs == NULL) {
- res = NULL;
- Py_DECREF(kwnames);
- goto fail;
- }
  for (int i = 0; i < kwcount; i++) {
  Py_INCREF(kws[2*i]);
  PyTuple_SET_ITEM(kwnames, i, kws[2*i]);
- kwargs[i] = kws[2*i+1];
  }
  PyFrameConstructor constr = {
  .fc_globals = globals,