Revert 34153: Py_UNICODE should not be signed.
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 30ae6f0..6d8f2e4 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -135,14 +135,9 @@
/* Resizing shared object (unicode_empty or single character
objects) in-place is not allowed. Use PyUnicode_Resize()
instead ! */
- if (unicode == unicode_empty ||
- (unicode->length == 1 &&
- /* MvL said unicode->str[] may be signed. Python generally assumes
- * an int contains at least 32 bits, and we don't use more than
- * 32 bits even in a UCS4 build, so casting to unsigned int should
- * be correct.
- */
- (unsigned int)unicode->str[0] < 256U &&
+ if (unicode == unicode_empty ||
+ (unicode->length == 1 &&
+ unicode->str[0] < 256U &&
unicode_latin1[unicode->str[0]] == unicode)) {
PyErr_SetString(PyExc_SystemError,
"can't resize shared unicode objects");