don't segfault when \N escapes are used and unicodedata fails to load
Fixes #4367
diff --git a/Lib/test/test_unicodedata.py b/Lib/test/test_unicodedata.py
index b24e8f7..84999e5 100644
--- a/Lib/test/test_unicodedata.py
+++ b/Lib/test/test_unicodedata.py
@@ -4,9 +4,13 @@
(c) Copyright CNRI, All Rights Reserved. NO WARRANTY.
-"""#"
-import unittest, test.test_support
+"""
+
+import sys
+import unittest
import hashlib
+import subprocess
+import test.test_support
encoding = 'utf-8'
@@ -196,6 +200,25 @@
class UnicodeMiscTest(UnicodeDatabaseTest):
+ def test_failed_import_during_compiling(self):
+ # Issue 4367
+ # Decoding \N escapes requires the unicodedata module. If it can't be
+ # imported, we shouldn't segfault.
+
+ # This program should raise a SyntaxError in the eval.
+ code = "import sys;" \
+ "sys.modules['unicodedata'] = None;" \
+ """eval("u'\N{SOFT HYPHEN}'")"""
+ args = [sys.executable, "-c", code]
+ # We use a subprocess because the unicodedata module may already have
+ # been loaded in this process.
+ popen = subprocess.Popen(args, stderr=subprocess.PIPE)
+ popen.wait()
+ self.assertEqual(popen.returncode, 1)
+ error = "SyntaxError: (unicode error) \N escapes not supported " \
+ "(can't load unicodedata module)"
+ self.assertTrue(error in popen.stderr.read())
+
def test_decimal_numeric_consistent(self):
# Test that decimal and numeric are consistent,
# i.e. if a character has a decimal value,
diff --git a/Misc/NEWS b/Misc/NEWS
index 1fcf319..d691d8c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,9 @@
Core and Builtins
-----------------
+- Issue #4367: Python would segfault during compiling when the unicodedata
+ module couldn't be imported and \N escapes were present.
+
- Issue #4233: Changed semantic of ``_fileio.FileIO``'s ``close()``
method on file objects with closefd=False. The file descriptor is still
kept open but the file object behaves like a closed file. The ``FileIO``
diff --git a/Python/ast.c b/Python/ast.c
index 6eb3aa4..02aa2a7 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -1294,13 +1294,14 @@
if (PyErr_ExceptionMatches(PyExc_UnicodeError)){
PyObject *type, *value, *tback, *errstr;
PyErr_Fetch(&type, &value, &tback);
- errstr = ((PyUnicodeErrorObject *)value)->reason;
+ errstr = PyObject_Str(value);
if (errstr) {
char *s = "";
char buf[128];
s = PyString_AsString(errstr);
PyOS_snprintf(buf, sizeof(buf), "(unicode error) %s", s);
ast_error(n, buf);
+ Py_DECREF(errstr);
} else {
ast_error(n, "(unicode error) unknown error");
}