Backport for bug fix of 2.204.

diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index 715c4649c6085945d676f3762f7b6f603d5ec18a..3985cd3191f8ee35dd9e13af54821cb38310de65 100644 (file)
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -1098,8 +1098,8 @@ PyErr_PrintEx(int set_sys_last_vars)
 void PyErr_Display(PyObject *exception, PyObject *value, PyObject *tb)
 {
        int err = 0;
-       PyObject *v = value;
        PyObject *f = PySys_GetObject("stderr");
+       Py_INCREF(value);
        if (f == NULL)
                fprintf(stderr, "lost sys.stderr\n");
        else {
@@ -1109,12 +1109,12 @@ void PyErr_Display(PyObject *exception, PyObject *value, PyObject *tb)
                if (tb && tb != Py_None)
                        err = PyTraceBack_Print(tb, f);
                if (err == 0 &&
-                   PyObject_HasAttrString(v, "print_file_and_line"))
+                   PyObject_HasAttrString(value, "print_file_and_line"))
                {
                        PyObject *message;
                        const char *filename, *text;
                        int lineno, offset;
-                       if (!parse_syntax_error(v, &message, &filename,
+                       if (!parse_syntax_error(value, &message, &filename,
                                                &lineno, &offset, &text))
                                PyErr_Clear();
                        else {
@@ -1130,7 +1130,8 @@ void PyErr_Display(PyObject *exception, PyObject *value, PyObject *tb)
                                PyFile_WriteString("\n", f);
                                if (text != NULL)
                                        print_error_text(f, offset, text);
-                               v = message;
+                               Py_DECREF(value);
+                               value = message;
                                /* Can't be bothered to check all those
                                   PyFile_WriteString() calls */
                                if (PyErr_Occurred())
@@ -1167,8 +1168,8 @@ void PyErr_Display(PyObject *exception, PyObject *value, PyObject *tb)
                else
                        err = PyFile_WriteObject(exception, f, Py_PRINT_RAW);
                if (err == 0) {
-                       if (v != NULL && v != Py_None) {
-                               PyObject *s = PyObject_Str(v);
+                       if (value != Py_None) {
+                               PyObject *s = PyObject_Str(value);
                                /* only print colon if the str() of the
                                   object is not the empty string
                                */
@@ -1185,6 +1186,7 @@ void PyErr_Display(PyObject *exception, PyObject *value, PyObject *tb)
                if (err == 0)
                        err = PyFile_WriteString("\n", f);
        }
+       Py_DECREF(value);
        /* If an error happened here, don't show it.
           XXX This is wrong, but too many callers rely on this behavior. */
        if (err != 0)