commit 61e40bd897da8ab4bf2dffe817d0163e984c1e40
author Martin v. Löwis <martin@v.loewis.de> Sat Apr 17 19:36:48 2004 +0000
committer Martin v. Löwis <martin@v.loewis.de> Sat Apr 17 19:36:48 2004 +0000
tree c8500cc600b30c400873e3c6c0a838d43b9d83fd
parent e5fced781bbf892a498bd2422b49d9ac1a2d6352

Special case normalization of empty strings. Fixes #924361.
Backported to 2.3.

Modules/unicodedata.c

diff --git a/Modules/unicodedata.c b/Modules/unicodedata.c
index 311db29..ba218a3 100644
--- a/Modules/unicodedata.c
+++ b/Modules/unicodedata.c
@@ -515,6 +515,13 @@
                          &form, &PyUnicode_Type, &input))
         return NULL;
 
+    if (PyUnicode_GetSize(input) == 0) {
+        /* Special case empty input strings, since resizing
+           them  later would cause internal errors. */
+        Py_INCREF(input);
+        return input;
+    }
+
     if (strcmp(form, "NFC") == 0)
         return nfc_nfkc(input, 0);
     if (strcmp(form, "NFKC") == 0)