From 57003f81ead9ff38150c1e4821811c66c296d33c Mon Sep 17 00:00:00 2001
From: Victor Stinner <victor.stinner@gmail.com>
Date: Tue, 15 Mar 2016 17:23:35 +0100
Subject: [PATCH] faulthandler: Test Py_FatalError() with GIL released

Issue #26558.
---
 Lib/test/test_faulthandler.py |  8 ++++++++
 Modules/faulthandler.c        | 12 ++++++++++--
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/Lib/test/test_faulthandler.py b/Lib/test/test_faulthandler.py
index 0d86cb5da81..12969d51843 100644
--- a/Lib/test/test_faulthandler.py
+++ b/Lib/test/test_faulthandler.py
@@ -185,6 +185,14 @@ class FaultHandlerTests(unittest.TestCase):
             2,
             'xyz')
 
+    def test_fatal_error_without_gil(self):
+        self.check_fatal_error("""
+            import faulthandler
+            faulthandler._fatal_error(b'xyz', True)
+            """,
+            2,
+            'xyz')
+
     @unittest.skipIf(sys.platform.startswith('openbsd') and HAVE_THREADS,
                      "Issue #12868: sigaltstack() doesn't work on "
                      "OpenBSD if Python is compiled with pthread")
diff --git a/Modules/faulthandler.c b/Modules/faulthandler.c
index 14384b5d1cf..45c9fcb2af5 100644
--- a/Modules/faulthandler.c
+++ b/Modules/faulthandler.c
@@ -935,10 +935,18 @@ static PyObject *
 faulthandler_fatal_error_py(PyObject *self, PyObject *args)
 {
     char *message;
-    if (!PyArg_ParseTuple(args, "y:fatal_error", &message))
+    int release_gil = 0;
+    if (!PyArg_ParseTuple(args, "y|i:fatal_error", &message, &release_gil))
         return NULL;
     faulthandler_suppress_crash_report();
-    Py_FatalError(message);
+    if (release_gil) {
+        Py_BEGIN_ALLOW_THREADS
+        Py_FatalError(message);
+        Py_END_ALLOW_THREADS
+    }
+    else {
+        Py_FatalError(message);
+    }
     Py_RETURN_NONE;
 }