#4122: On Windows, Py_UNICODE_ISSPACE cannot be used in an extension module:
compilation fails with "undefined reference to _Py_ascii_whitespace"
Will backport to 2.6.
diff --git a/Include/unicodeobject.h b/Include/unicodeobject.h
index 057f770..ee9fec1 100644
--- a/Include/unicodeobject.h
+++ b/Include/unicodeobject.h
@@ -354,7 +354,7 @@
in most situations is solely ASCII whitespace, we optimize for the common
case by using a quick look-up table with an inlined check.
*/
-extern const unsigned char _Py_ascii_whitespace[];
+PyAPI_DATA(const unsigned char) _Py_ascii_whitespace[];
#define Py_UNICODE_ISSPACE(ch) \
((ch) < 128U ? _Py_ascii_whitespace[(ch)] : _PyUnicode_IsWhitespace(ch))