diff --git a/Lib/test/script_helper.py b/Lib/test/script_helper.py
--- a/Lib/test/script_helper.py
+++ b/Lib/test/script_helper.py
@@ -16,7 +16,8 @@
 from test.support import make_legacy_pyc, strip_python_stderr
 
 # Executing the interpreter in a subprocess
-def _assert_python(expected_success, *args, **env_vars):
+def _assert_python(expected_success, *args, preexec_fn=None,
+                   **env_vars):
     cmd_line = [sys.executable]
     if not env_vars:
         cmd_line.append('-E')
@@ -31,7 +32,7 @@
     cmd_line.extend(args)
     p = subprocess.Popen(cmd_line, stdin=subprocess.PIPE,
                          stdout=subprocess.PIPE, stderr=subprocess.PIPE,
-                         env=env)
+                         env=env, preexec_fn=preexec_fn)
     try:
         out, err = p.communicate()
     finally:
diff --git a/Lib/test/test_faulthandler.py b/Lib/test/test_faulthandler.py
--- a/Lib/test/test_faulthandler.py
+++ b/Lib/test/test_faulthandler.py
@@ -48,7 +48,8 @@
         support.unlink(filename)
 
 class FaultHandlerTests(unittest.TestCase):
-    def get_output(self, code, filename=None):
+    def get_output(self, expect_success, code, filename=None,
+                   extra_args=(), env_vars={}):
         """
         Run the specified code in Python (in a new child process) and read the
         output from the standard error or from a file (if filename is set).
@@ -58,13 +59,12 @@
         build, and replace "Current thread 0x00007f8d8fbd9700" by "Current
         thread XXX".
         """
-        options = {}
-        if prepare_subprocess:
-            options['preexec_fn'] = prepare_subprocess
-        process = script_helper.spawn_python('-c', code, **options)
-        stdout, stderr = process.communicate()
-        exitcode = process.wait()
-        output = support.strip_python_stderr(stdout)
+
+        args = list(extra_args) + ['-c', code]
+        exitcode, stdout, stderr = script_helper._assert_python(
+            expect_success, *args, preexec_fn=prepare_subprocess, **env_vars)
+
+        output = support.strip_python_stderr(stderr)
         output = output.decode('ascii', 'backslashreplace')
         if filename:
             self.assertEqual(output, '')
@@ -77,7 +77,8 @@
         return output.splitlines(), exitcode
 
     def check_fatal_error(self, code, line_number, name_regex,
-                          filename=None, all_threads=True, other_regex=None):
+                          filename=None, all_threads=True, other_regex=None,
+                          extra_args=(), env_vars={}):
         """
         Check that the fault handler for fatal errors is enabled and check the
         traceback from the child process output.
@@ -100,10 +101,28 @@
             header=re.escape(header))
         if other_regex:
             regex += '|' + other_regex
-        output, exitcode = self.get_output(code, filename)
+        output, exitcode = self.get_output(False, code, filename,
+                                           extra_args, env_vars)
         output = '\n'.join(output)
         self.assertRegex(output, regex)
-        self.assertNotEqual(exitcode, 0)
+
+    def test_X_option(self):
+        self.check_fatal_error("""
+import faulthandler
+faulthandler._sigsegv()
+""".strip(),
+            2,
+            'Segmentation fault',
+            extra_args=['-X', 'faulthandler'])
+
+    def test_env_var(self):
+        self.check_fatal_error("""
+import sys, os, faulthandler
+faulthandler._sigsegv()
+""".strip(),
+            2,
+            'Segmentation fault',
+            env_vars={'PYTHONFAULTHANDLER':'YesPlease'})
 
     def test_read_null(self):
         self.check_fatal_error("""
@@ -228,11 +247,10 @@
 faulthandler._read_null()
 """.strip()
         not_expected = 'Fatal Python error'
-        stderr, exitcode = self.get_output(code)
+        stderr, exitcode = self.get_output(False, code)
         stder = '\n'.join(stderr)
         self.assertTrue(not_expected not in stderr,
                      "%r is present in %r" % (not_expected, stderr))
-        self.assertNotEqual(exitcode, 0)
 
     def test_is_enabled(self):
         orig_stderr = sys.stderr
@@ -290,9 +308,8 @@
             '  File "<string>", line 11 in funcA',
             '  File "<string>", line 13 in <module>'
         ]
-        trace, exitcode = self.get_output(code, filename)
+        trace, exitcode = self.get_output(True, code, filename)
         self.assertEqual(trace, expected)
-        self.assertEqual(exitcode, 0)
 
     def test_dump_traceback(self):
         self.check_dump_traceback(None)
@@ -340,7 +357,7 @@
 waiter.join()
 """.strip()
         code = code.format(filename=repr(filename))
-        output, exitcode = self.get_output(code, filename)
+        output, exitcode = self.get_output(True, code, filename)
         output = '\n'.join(output)
         if filename:
             lineno = 8
@@ -359,7 +376,6 @@
 """.strip()
         regex = regex.format(lineno=lineno)
         self.assertRegex(output, regex)
-        self.assertEqual(exitcode, 0)
 
     def test_dump_traceback_threads(self):
         self.check_dump_traceback_threads(None)
@@ -409,7 +425,7 @@
             has_filename=bool(filename),
             filename=repr(filename),
         )
-        trace, exitcode = self.get_output(code, filename)
+        trace, exitcode = self.get_output(True, code, filename)
         trace = '\n'.join(trace)
 
         if not cancel:
@@ -421,7 +437,6 @@
             self.assertRegex(trace, regex)
         else:
             self.assertEqual(trace, '')
-        self.assertEqual(exitcode, 0)
 
     @unittest.skipIf(not hasattr(faulthandler, 'dump_tracebacks_later'),
                      'need faulthandler.dump_tracebacks_later()')
@@ -514,7 +529,7 @@
             unregister=unregister,
             chain=chain,
         )
-        trace, exitcode = self.get_output(code, filename)
+        trace, exitcode = self.get_output(not unregister, code, filename)
         trace = '\n'.join(trace)
         if not unregister:
             if all_threads:
@@ -525,10 +540,6 @@
             self.assertRegex(trace, regex)
         else:
             self.assertEqual(trace, '')
-        if unregister:
-            self.assertNotEqual(exitcode, 0)
-        else:
-            self.assertEqual(exitcode, 0)
 
     def test_register(self):
         self.check_register()