# HG changeset patch
# Parent e3ba7e1dd4060444080f6772ee8c4942f6f5854b

diff -r e3ba7e1dd406 Python/traceback.c
--- a/Python/traceback.c	Wed Dec 28 12:01:51 2011 -0600
+++ b/Python/traceback.c	Thu Dec 29 18:05:40 2011 +0000
@@ -380,6 +380,7 @@
     int err;
     PyObject *limitv;
     long limit = PyTraceBack_LIMIT;
+    PyObject *exc_type, *exc_value, *exc_tb;
 
     if (v == NULL)
         return 0;
@@ -387,11 +388,9 @@
         PyErr_BadInternalCall();
         return -1;
     }
+    PyErr_Fetch(&exc_type, &exc_value, &exc_tb);
     limitv = PySys_GetObject("tracebacklimit");
     if (limitv) {
-        PyObject *exc_type, *exc_value, *exc_tb;
-
-        PyErr_Fetch(&exc_type, &exc_value, &exc_tb);
         limit = PyLong_AsLong(limitv);
         if (limit == -1 && PyErr_Occurred()) {
             if (PyErr_ExceptionMatches(PyExc_OverflowError)) {
@@ -407,11 +406,24 @@
         else if (limit <= 0) {
             limit = PyTraceBack_LIMIT;
         }
-        PyErr_Restore(exc_type, exc_value, exc_tb);
+    }
+    /* PyFile_WriteString() calls PyErr_Occurred() and indirectly
+       calls PyErr_CheckSignals().  It fails if either function
+       returns a non-zero result. Therefore we should first call
+       PyErr_CheckSignals() and clear the current exception.  See
+       Issue 13673. */
+    PyErr_CheckSignals();
+    if (PyErr_Occurred()) {
+        if (exc_type == NULL)
+            PyErr_Fetch(&exc_type, &exc_value, &exc_tb);
+        else
+            PyErr_Clear();
     }
     err = PyFile_WriteString("Traceback (most recent call last):\n", f);
     if (!err)
         err = tb_printinternal((PyTracebackObject *)v, f, limit);
+    if (exc_type != NULL)
+        PyErr_Restore(exc_type, exc_value, exc_tb);
     return err;
 }