Merged revisions 77576 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r77576 | antoine.pitrou | 2010-01-17 13:38:54 +0100 (dim., 17 janv. 2010) | 12 lines

  Merged revisions 77573 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

  ........
    r77573 | antoine.pitrou | 2010-01-17 13:26:20 +0100 (dim., 17 janv. 2010) | 6 lines

    Issue #7561: Operations on empty bytearrays (such as `int(bytearray())`)
    could crash in many places because of the PyByteArray_AS_STRING() macro
    returning NULL.  The macro now returns a statically allocated empty
    string instead.
  ........
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diff --git a/Include/bytearrayobject.h b/Include/bytearrayobject.h
index 265b4bb..8702e5a 100644
--- a/Include/bytearrayobject.h
+++ b/Include/bytearrayobject.h
@@ -44,9 +44,13 @@
 PyAPI_FUNC(int) PyByteArray_Resize(PyObject *, Py_ssize_t);
 
 /* Macros, trading safety for speed */
-#define PyByteArray_AS_STRING(self) (assert(PyByteArray_Check(self)),((PyByteArrayObject *)(self))->ob_bytes)
+#define PyByteArray_AS_STRING(self) \
+    (assert(PyByteArray_Check(self)), \
+     Py_SIZE(self) ? ((PyByteArrayObject *)(self))->ob_bytes : _PyByteArray_empty_string)
 #define PyByteArray_GET_SIZE(self)  (assert(PyByteArray_Check(self)),Py_SIZE(self))
 
+extern char _PyByteArray_empty_string[];
+
 #ifdef __cplusplus
 }
 #endif