diff -r d489394a73de Python/modsupport.c
--- a/Python/modsupport.c	Tue Dec 17 15:12:46 2013 +0200
+++ b/Python/modsupport.c	Thu Dec 19 12:10:35 2013 +0100
@@ -161,7 +161,17 @@ do_mktuple(const char **p_format, va_lis
     /* Note that we can't bail immediately on error as this will leak
        refcounts on any 'N' arguments. */
     for (i = 0; i < n; i++) {
-        PyObject *w = do_mkvalue(p_format, p_va, flags);
+        PyObject *w;
+
+        if (itemfailed) {
+            PyObject *exception, *value, *tb;
+            PyErr_Fetch(&exception, &value, &tb);
+            w = do_mkvalue(p_format, p_va, flags);
+            PyErr_Restore(exception, value, tb);
+        }
+        else {
+            w = do_mkvalue(p_format, p_va, flags);
+        }
         if (w == NULL) {
             itemfailed = 1;
             Py_INCREF(Py_None);