Make identifiers str (not str8) objects throughout. This affects the parser, various object implementations, and all places that put identifiers into C string literals. In testing, a number of crashes occurred as code would fail when the recursion limit was reached (such as the Unicode interning dictionary having key/value pairs where key is not value). To solve these, I added an overflowed flag, which allows for 50 more recursions after the limit was reached and the exception was raised, and a recursion_critical flag, which indicates that recursion absolutely must be allowed, i.e. that a certain call must not cause a stack overflow exception. There are still some places where both str and str8 are accepted as identifiers; these should eventually be removed.

--- a/Objects/methodobject.c	Sat Jun 09 16:13:23 2007 +0000
+++ b/Objects/methodobject.c	Sun Jun 10 09:51:05 2007 +0000
@@ -143,7 +143,7 @@
 static PyObject *
 meth_get__name__(PyCFunctionObject *m, void *closure)
 {
-	return PyString_FromString(m->m_ml->ml_name);
+	return PyUnicode_FromString(m->m_ml->ml_name);
 }
 
 static int
@@ -297,7 +297,7 @@
 	i = 0;
 	for (c = chain; c != NULL; c = c->link) {
 		for (ml = c->methods; ml->ml_name != NULL; ml++) {
-			PyList_SetItem(v, i, PyString_FromString(ml->ml_name));
+			PyList_SetItem(v, i, PyUnicode_FromString(ml->ml_name));
 			i++;
 		}
 	}