Added the const qualifier to char* variables that refer to readonly internal
UTF-8 represenatation of Unicode objects.
diff --git a/Modules/_sqlite/row.c b/Modules/_sqlite/row.c
index 53342f3..c6c3e98 100644
--- a/Modules/_sqlite/row.c
+++ b/Modules/_sqlite/row.c
@@ -79,12 +79,12 @@
 PyObject* pysqlite_row_subscript(pysqlite_Row* self, PyObject* idx)
 {
     Py_ssize_t _idx;
-    char* key;
+    const char *key;
     Py_ssize_t nitems, i;
-    char* compare_key;
+    const char *compare_key;
 
-    char* p1;
-    char* p2;
+    const char *p1;
+    const char *p2;
 
     PyObject* item;