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.
diff --git a/Include/stringobject.h b/Include/stringobject.h
index 2b8cc2f..0a932f0 100644
--- a/Include/stringobject.h
+++ b/Include/stringobject.h
@@ -84,8 +84,8 @@
#define PyString_CHECK_INTERNED(op) (((PyStringObject *)(op))->ob_sstate)
/* Macro, trading safety for speed */
-#define PyString_AS_STRING(op) (((PyStringObject *)(op))->ob_sval)
-#define PyString_GET_SIZE(op) (((PyStringObject *)(op))->ob_size)
+#define PyString_AS_STRING(op) (assert(PyString_Check(op)),(((PyStringObject *)(op))->ob_sval))
+#define PyString_GET_SIZE(op) (assert(PyString_Check(op)),(((PyStringObject *)(op))->ob_size))
/* _PyString_Join(sep, x) is like sep.join(x). sep must be PyStringObject*,
x must be an iterable object. */