bpo-35461: Document C API functions which suppress exceptions. (GH-11119)

Doc/c-api/dict.rst

@@ -95,6 +95,10 @@ Dictionary Objects
    Return the object from dictionary *p* which has a key *key*.  Return *NULL*
    if the key *key* is not present, but *without* setting an exception.
 
+   Note that exceptions which occur while calling :meth:`__hash__` and
+   :meth:`__eq__` methods will get suppressed.
+   To get error reporting use :c:func:`PyDict_GetItemWithError()` instead.
+
 
 .. c:function:: PyObject* PyDict_GetItemWithError(PyObject *p, PyObject *key)
 
@@ -109,6 +113,11 @@ Dictionary Objects
    This is the same as :c:func:`PyDict_GetItem`, but *key* is specified as a
    :c:type:`const char\*`, rather than a :c:type:`PyObject\*`.
 
+   Note that exceptions which occur while calling :meth:`__hash__` and
+   :meth:`__eq__` methods and creating a temporary string object
+   will get suppressed.
+   To get error reporting use :c:func:`PyDict_GetItemWithError()` instead.
+
 
 .. c:function:: PyObject* PyDict_SetDefault(PyObject *p, PyObject *key, PyObject *default)