Based on patches by Todd.Rovito and Phil Webster.

Initial patch by Madison May.

Initial patch by Madison May.

There is more to be done here in terms of accepting RFC invalid
input that some mailers accept, but this covers the valid
RFC places where encoded words can occur in structured headers.

building Python but having some optional module which didn't build.

Patch by Yogesh Chaudhari.

...`` when an ImportError occurs.

Other cases had already been switched over to using the repr.

Thanks to Tomasz Maćkowiak for the patch.

constants in importlib._bootstrap. Along the way clean up from string
interpolation to use the repr explicitly.

Initial patch by Madison May.

* Use Py_DECREF() instead of PyObject_GC_Del() to release correctly all
  resources
* Raise MemoryError on memory allocation failure

allocation failure

Handle PyLong_FromLong() and PyUnicode_FromString() failures

on memory allocation failure

Instead of ignoring the memory allocation failure and create invalid objects.

allocating a bigger table failed

PyMemoTable destructor does crash if mt_table is NULL.

memory allocation failure

Replace also PyMem_Free() with PyMem_FREE() to be consistent with the rest of
the function.

fails with an assertion error

exception (when getting NULL) to an assertion to detect bugs earlier

the newly created pickler, and not PyObject_GC_Del().

raised if the result is NULL to help to find bugs in C mode (get the error
earlier than the SystemError in ceval.c).

The caller gets an error code and can raise a classic Python exception.

 * create_new_element() initializes all attributes before handling errors,
   to fix a crash in the destructor
* create_new_element() calls PyObject_GC_Del() on error, instead of
  PyObject_Del(), because the object was created by PyObject_GC_New()
* subelement() now handles create_new_element() failure
* element_getattro() now handles element_get_text() failure
* makeuniversal() now handles PyBytes_FromStringAndSize() failure

attributes before handling errors

_Pickler_New() now calls PyObject_GC_Del() instead of Py_DECREF() on error,
because the pickle object is created using PyObject_GC_New().

Fix a crash in the destructor when an attribute is not initiallized.