Added the const qualifier to char* variables that refer to readonly internal
UTF-8 represenatation of Unicode objects.
diff --git a/Python/structmember.c b/Python/structmember.c
index be2737d..e653d02 100644
--- a/Python/structmember.c
+++ b/Python/structmember.c
@@ -249,7 +249,7 @@
         Py_XDECREF(oldv);
         break;
     case T_CHAR: {
-        char *string;
+        const char *string;
         Py_ssize_t len;
 
         string = PyUnicode_AsUTF8AndSize(v, &len);