diff --git a/Lib/test/test_capi.py b/Lib/test/test_capi.py
index e65973c..ff18a21 100644
--- a/Lib/test/test_capi.py
+++ b/Lib/test/test_capi.py
@@ -61,8 +61,8 @@
         self.assertEqual(out, b'')
         # This used to cause an infinite loop.
         self.assertTrue(err.rstrip().startswith(
-                         b'Fatal Python error:'
-                         b' PyThreadState_Get: no current thread'))
+                         b'Fatal Python error: '
+                         b'PyThreadState_Get: no current thread'))
 
     def test_memoryview_from_NULL_pointer(self):
         self.assertRaises(ValueError, _testcapi.make_memoryview_from_NULL_pointer)
@@ -197,7 +197,8 @@
             """)
             rc, out, err = assert_python_failure('-c', code)
             self.assertRegex(err.replace(b'\r', b''),
-                             br'Fatal Python error: a function returned NULL '
+                             br'Fatal Python error: _Py_CheckFunctionResult: '
+                                br'a function returned NULL '
                                 br'without setting an error\n'
                              br'Python runtime state: initialized\n'
                              br'SystemError: <built-in function '
@@ -225,8 +226,9 @@
             """)
             rc, out, err = assert_python_failure('-c', code)
             self.assertRegex(err.replace(b'\r', b''),
-                             br'Fatal Python error: a function returned a '
-                                br'result with an error set\n'
+                             br'Fatal Python error: _Py_CheckFunctionResult: '
+                                 br'a function returned a result '
+                                 br'with an error set\n'
                              br'Python runtime state: initialized\n'
                              br'ValueError\n'
                              br'\n'
@@ -668,7 +670,7 @@
                  r"\n"
                  r"Enable tracemalloc to get the memory block allocation traceback\n"
                  r"\n"
-                 r"Fatal Python error: bad trailing pad byte")
+                 r"Fatal Python error: _PyMem_DebugRawFree: bad trailing pad byte")
         regex = regex.format(ptr=self.PTR_REGEX)
         regex = re.compile(regex, flags=re.DOTALL)
         self.assertRegex(out, regex)
@@ -684,14 +686,14 @@
                  r"\n"
                  r"Enable tracemalloc to get the memory block allocation traceback\n"
                  r"\n"
-                 r"Fatal Python error: bad ID: Allocated using API 'm', verified using API 'r'\n")
+                 r"Fatal Python error: _PyMem_DebugRawFree: bad ID: Allocated using API 'm', verified using API 'r'\n")
         regex = regex.format(ptr=self.PTR_REGEX)
         self.assertRegex(out, regex)
 
     def check_malloc_without_gil(self, code):
         out = self.check(code)
-        expected = ('Fatal Python error: Python memory allocator called '
-                    'without holding the GIL')
+        expected = ('Fatal Python error: _PyMem_DebugMalloc: '
+                    'Python memory allocator called without holding the GIL')
         self.assertIn(expected, out)
 
     def test_pymem_malloc_without_gil(self):
diff --git a/Lib/test/test_exceptions.py b/Lib/test/test_exceptions.py
index 22a2236..2d3a13a 100644
--- a/Lib/test/test_exceptions.py
+++ b/Lib/test/test_exceptions.py
@@ -1078,8 +1078,9 @@
         """
         with SuppressCrashReport():
             rc, out, err = script_helper.assert_python_failure("-c", code)
-            self.assertIn(b'Fatal Python error: Cannot recover from '
-                          b'MemoryErrors while normalizing exceptions.', err)
+            self.assertIn(b'Fatal Python error: _PyErr_NormalizeException: '
+                          b'Cannot recover from MemoryErrors while '
+                          b'normalizing exceptions.', err)
 
     @cpython_only
     def test_MemoryError(self):
diff --git a/Lib/test/test_faulthandler.py b/Lib/test/test_faulthandler.py
index ac8cf46..c64afe8 100644
--- a/Lib/test/test_faulthandler.py
+++ b/Lib/test/test_faulthandler.py
@@ -123,7 +123,9 @@
         self.assertRegex(output, regex)
         self.assertNotEqual(exitcode, 0)
 
-    def check_fatal_error(self, code, line_number, name_regex, **kw):
+    def check_fatal_error(self, code, line_number, name_regex, func=None, **kw):
+        if func:
+            name_regex = '%s: %s' % (func, name_regex)
         fatal_error = 'Fatal Python error: %s' % name_regex
         self.check_error(code, line_number, fatal_error, **kw)
 
@@ -173,6 +175,7 @@
             3,
             'in new thread',
             know_current_thread=False,
+            func='faulthandler_fatal_error_thread',
             py_fatal_error=True)
 
     def test_sigabrt(self):
@@ -230,6 +233,7 @@
             """,
             2,
             'xyz',
+            func='faulthandler_fatal_error_py',
             py_fatal_error=True)
 
     def test_fatal_error_without_gil(self):
@@ -239,6 +243,7 @@
             """,
             2,
             'xyz',
+            func='faulthandler_fatal_error_py',
             py_fatal_error=True)
 
     @unittest.skipIf(sys.platform.startswith('openbsd'),
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index 4a7cbe5..fe07b56 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -4247,7 +4247,8 @@
         err = res.err.decode()
         if res.rc != 0:
             # Failure: should be a fatal error
-            pattern = (r"Fatal Python error: could not acquire lock "
+            pattern = (r"Fatal Python error: _enter_buffered_busy: "
+                       r"could not acquire lock "
                        r"for <(_io\.)?BufferedWriter name='<{stream_name}>'> "
                        r"at interpreter shutdown, possibly due to "
                        r"daemon threads".format_map(locals()))
diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
index c5bd8a4..027f87e 100644
--- a/Lib/test/test_sys.py
+++ b/Lib/test/test_sys.py
@@ -269,6 +269,8 @@
         finally:
             sys.setrecursionlimit(oldlimit)
 
+    # The error message is specific to CPython
+    @test.support.cpython_only
     def test_recursionlimit_fatalerror(self):
         # A fatal error occurs if a second recursion limit is hit when recovering
         # from a first one.
@@ -290,7 +292,8 @@
                 err = sub.communicate()[1]
                 self.assertTrue(sub.returncode, sub.returncode)
                 self.assertIn(
-                    b"Fatal Python error: Cannot recover from stack overflow",
+                    b"Fatal Python error: _Py_CheckRecursiveCall: "
+                    b"Cannot recover from stack overflow",
                     err)
 
     def test_getwindowsversion(self):