diff --git a/Lib/test/_test_multiprocessing.py b/Lib/test/_test_multiprocessing.py
index 3ae0cb976863d1..bcbf5676b2e3a3 100644
--- a/Lib/test/_test_multiprocessing.py
+++ b/Lib/test/_test_multiprocessing.py
@@ -69,6 +69,12 @@
     msvcrt = None
 
 
+if support.check_sanitizer(address=True):
+    # bpo-45200: Skip multiprocessing tests if Python is built with ASAN to
+    # work around a libasan race condition: dead lock in pthread_create().
+    raise unittest.SkipTest("libasan has a pthread_create() dead lock")
+
+
 def latin(s):
     return s.encode('latin')
 
diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index 53804f13fc8a20..c4115a850b2e44 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -54,7 +54,7 @@
     "requires_IEEE_754", "skip_unless_xattr", "requires_zlib",
     "anticipate_failure", "load_package_tests", "detect_api_mismatch",
     "check__all__", "skip_if_buggy_ucrt_strfptime",
-    "ignore_warnings",
+    "ignore_warnings", "check_sanitizer", "skip_if_sanitizer",
     # sys
     "is_jython", "is_android", "check_impl_detail", "unix_shell",
     "setswitchinterval",
@@ -644,6 +644,41 @@ def wrapper(*args, **kw):
     return decorator
 
 
+def check_sanitizer(*, address=False, memory=False, ub=False):
+    """Returns True if Python is compiled with sanitizer support"""
+    if not (address or memory or ub):
+        raise ValueError('At least one of address, memory, or ub must be True')
+
+
+    _cflags = sysconfig.get_config_var('CFLAGS') or ''
+    _config_args = sysconfig.get_config_var('CONFIG_ARGS') or ''
+    memory_sanitizer = (
+        '-fsanitize=memory' in _cflags or
+        '--with-memory-sanitizer' in _config_args
+    )
+    address_sanitizer = (
+        '-fsanitize=address' in _cflags or
+        '--with-memory-sanitizer' in _config_args
+    )
+    ub_sanitizer = (
+        '-fsanitize=undefined' in _cflags or
+        '--with-undefined-behavior-sanitizer' in _config_args
+    )
+    return (
+        (memory and memory_sanitizer) or
+        (address and address_sanitizer) or
+        (ub and ub_sanitizer)
+    )
+
+
+def skip_if_sanitizer(reason=None, *, address=False, memory=False, ub=False):
+    """Decorator raising SkipTest if running with a sanitizer active."""
+    if not reason:
+        reason = 'not working with sanitizers active'
+    skip = check_sanitizer(address=address, memory=memory, ub=ub)
+    return unittest.skipIf(skip, reason)
+
+
 def system_must_validate_cert(f):
     """Skip the test on TLS certificate validation failures."""
     @functools.wraps(f)
diff --git a/Lib/test/test___all__.py b/Lib/test/test___all__.py
index 0ba243ee4e74e4..7e1f80f2512565 100644
--- a/Lib/test/test___all__.py
+++ b/Lib/test/test___all__.py
@@ -4,6 +4,13 @@
 import sys
 
 
+if support.check_sanitizer(address=True, memory=True):
+    # bpo-46633: test___all__ is skipped because importing some modules
+    # directly can trigger known problems with ASAN (like tk or crypt).
+    raise unittest.SkipTest("workaround ASAN build issues on loading tests "
+                            "like tk or crypt")
+
+
 class NoAll(RuntimeError):
     pass
 
diff --git a/Lib/test/test_concurrent_futures.py b/Lib/test/test_concurrent_futures.py
index d693fb4ee199bb..d421b02754cf57 100644
--- a/Lib/test/test_concurrent_futures.py
+++ b/Lib/test/test_concurrent_futures.py
@@ -32,6 +32,12 @@
 import multiprocessing.util
 
 
+if support.check_sanitizer(address=True, memory=True):
+    # bpo-46633: Skip the test because it is too slow when Python is built
+    # with ASAN/MSAN: between 5 and 20 minutes on GitHub Actions.
+    raise unittest.SkipTest("test too slow on ASAN/MSAN build")
+
+
 def create_future(state=PENDING, exception=None, result=None):
     f = Future()
     f._state = state
diff --git a/Lib/test/test_crypt.py b/Lib/test/test_crypt.py
index 5dc83b4ecbfa00..877c575c5534ae 100644
--- a/Lib/test/test_crypt.py
+++ b/Lib/test/test_crypt.py
@@ -1,8 +1,11 @@
 import sys
 import unittest
+from test.support import check_sanitizer
 
 
 try:
+    if check_sanitizer(address=True, memory=True):
+        raise unittest.SkipTest("The crypt module SEGFAULTs on ASAN/MSAN builds")
     import crypt
     IMPORT_ERROR = None
 except ImportError as ex:
diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index 3f30a935d583c3..58f4df3060169c 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -33,24 +33,14 @@
 import numbers
 import locale
 from test.support import (run_unittest, run_doctest, is_resource_enabled,
-                          requires_IEEE_754, requires_docstrings)
-from test.support import (import_fresh_module, TestFailed,
+                          requires_IEEE_754, requires_docstrings,
+                          import_fresh_module, TestFailed,
                           run_with_locale, cpython_only,
-                          darwin_malloc_err_warning)
+                          darwin_malloc_err_warning,
+                          check_sanitizer)
 import random
 import inspect
 import threading
-import sysconfig
-_cflags = sysconfig.get_config_var('CFLAGS') or ''
-_config_args = sysconfig.get_config_var('CONFIG_ARGS') or ''
-MEMORY_SANITIZER = (
-    '-fsanitize=memory' in _cflags or
-    '--with-memory-sanitizer' in _config_args
-)
-
-ADDRESS_SANITIZER = (
-    '-fsanitize=address' in _cflags
-)
 
 
 if sys.platform == 'darwin':
@@ -5497,7 +5487,8 @@ def __abs__(self):
     # Issue 41540:
     @unittest.skipIf(sys.platform.startswith("aix"),
                      "AIX: default ulimit: test is flaky because of extreme over-allocation")
-    @unittest.skipIf(MEMORY_SANITIZER or ADDRESS_SANITIZER, "sanitizer defaults to crashing "
+    @unittest.skipIf(check_sanitizer(address=True, memory=True),
+                     "ASAN/MSAN sanitizer defaults to crashing "
                      "instead of returning NULL for malloc failure.")
     def test_maxcontext_exact_arith(self):
 
diff --git a/Lib/test/test_faulthandler.py b/Lib/test/test_faulthandler.py
index c64afe88c25d6c..2f8f5eec475f15 100644
--- a/Lib/test/test_faulthandler.py
+++ b/Lib/test/test_faulthandler.py
@@ -5,9 +5,9 @@
 import signal
 import subprocess
 import sys
-import sysconfig
 from test import support
 from test.support import script_helper, is_android
+from test.support import skip_if_sanitizer
 import tempfile
 import unittest
 from textwrap import dedent
@@ -19,16 +19,6 @@
 
 TIMEOUT = 0.5
 MS_WINDOWS = (os.name == 'nt')
-_cflags = sysconfig.get_config_var('CFLAGS') or ''
-_config_args = sysconfig.get_config_var('CONFIG_ARGS') or ''
-UB_SANITIZER = (
-    '-fsanitize=undefined' in _cflags or
-    '--with-undefined-behavior-sanitizer' in _config_args
-)
-MEMORY_SANITIZER = (
-    '-fsanitize=memory' in _cflags or
-    '--with-memory-sanitizer' in _config_args
-)
 
 
 def expected_traceback(lineno1, lineno2, header, min_count=1):
@@ -271,8 +261,8 @@ def test_gil_released(self):
             3,
             'Segmentation fault')
 
-    @unittest.skipIf(UB_SANITIZER or MEMORY_SANITIZER,
-                     "sanitizer builds change crashing process output.")
+    @skip_if_sanitizer(memory=True, ub=True, reason="sanitizer "
+                       "builds change crashing process output.")
     @skip_segfault_on_android
     def test_enable_file(self):
         with temporary_filename() as filename:
@@ -288,8 +278,8 @@ def test_enable_file(self):
 
     @unittest.skipIf(sys.platform == "win32",
                      "subprocess doesn't support pass_fds on Windows")
-    @unittest.skipIf(UB_SANITIZER or MEMORY_SANITIZER,
-                     "sanitizer builds change crashing process output.")
+    @skip_if_sanitizer(memory=True, ub=True, reason="sanitizer "
+                       "builds change crashing process output.")
     @skip_segfault_on_android
     def test_enable_fd(self):
         with tempfile.TemporaryFile('wb+') as fp:
diff --git a/Lib/test/test_idle.py b/Lib/test/test_idle.py
index 310b72c1d72e74..c747b02f643069 100644
--- a/Lib/test/test_idle.py
+++ b/Lib/test/test_idle.py
@@ -1,5 +1,9 @@
 import unittest
 from test.support import import_module
+from test.support import check_sanitizer
+
+if check_sanitizer(address=True, memory=True):
+    raise unittest.SkipTest("Tests involvin libX11 can SEGFAULT on ASAN/MSAN builds")
 
 # Skip test_idle if _tkinter wasn't built, if tkinter is missing,
 # if tcl/tk is not the 8.5+ needed for ttk widgets,
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index 49463e54e3c721..feee861830e405 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -28,7 +28,6 @@
 import random
 import signal
 import sys
-import sysconfig
 import textwrap
 import threading
 import time
@@ -40,7 +39,7 @@
 from test import support
 from test.support.script_helper import (
     assert_python_ok, assert_python_failure, run_python_until_end)
-from test.support import FakePath
+from test.support import FakePath, skip_if_sanitizer
 
 import codecs
 import io  # C implementation of io
@@ -62,17 +61,6 @@ def byteslike(*pos, **kw):
     class EmptyStruct(ctypes.Structure):
         pass
 
-_cflags = sysconfig.get_config_var('CFLAGS') or ''
-_config_args = sysconfig.get_config_var('CONFIG_ARGS') or ''
-MEMORY_SANITIZER = (
-    '-fsanitize=memory' in _cflags or
-    '--with-memory-sanitizer' in _config_args
-)
-
-ADDRESS_SANITIZER = (
-    '-fsanitize=address' in _cflags
-)
-
 # Does io.IOBase finalizer log the exception if the close() method fails?
 # The exception is ignored silently by default in release build.
 IOBASE_EMITS_UNRAISABLE = (hasattr(sys, "gettotalrefcount") or sys.flags.dev_mode)
@@ -1543,8 +1531,8 @@ def test_truncate_on_read_only(self):
 class CBufferedReaderTest(BufferedReaderTest, SizeofTest):
     tp = io.BufferedReader
 
-    @unittest.skipIf(MEMORY_SANITIZER or ADDRESS_SANITIZER, "sanitizer defaults to crashing "
-                     "instead of returning NULL for malloc failure.")
+    @skip_if_sanitizer(memory=True, address=True, reason= "sanitizer defaults to crashing "
+                       "instead of returning NULL for malloc failure.")
     def test_constructor(self):
         BufferedReaderTest.test_constructor(self)
         # The allocation can succeed on 32-bit builds, e.g. with more
@@ -1892,8 +1880,8 @@ def test_slow_close_from_thread(self):
 class CBufferedWriterTest(BufferedWriterTest, SizeofTest):
     tp = io.BufferedWriter
 
-    @unittest.skipIf(MEMORY_SANITIZER or ADDRESS_SANITIZER, "sanitizer defaults to crashing "
-                     "instead of returning NULL for malloc failure.")
+    @skip_if_sanitizer(memory=True, address=True, reason= "sanitizer defaults to crashing "
+                       "instead of returning NULL for malloc failure.")
     def test_constructor(self):
         BufferedWriterTest.test_constructor(self)
         # The allocation can succeed on 32-bit builds, e.g. with more
@@ -2391,8 +2379,8 @@ def test_interleaved_readline_write(self):
 class CBufferedRandomTest(BufferedRandomTest, SizeofTest):
     tp = io.BufferedRandom
 
-    @unittest.skipIf(MEMORY_SANITIZER or ADDRESS_SANITIZER, "sanitizer defaults to crashing "
-                     "instead of returning NULL for malloc failure.")
+    @skip_if_sanitizer(memory=True, address=True, reason= "sanitizer defaults to crashing "
+                       "instead of returning NULL for malloc failure.")
     def test_constructor(self):
         BufferedRandomTest.test_constructor(self)
         # The allocation can succeed on 32-bit builds, e.g. with more
diff --git a/Lib/test/test_peg_generator/__init__.py b/Lib/test/test_peg_generator/__init__.py
index fa855f2104c586..77f72fcc7c6e3b 100644
--- a/Lib/test/test_peg_generator/__init__.py
+++ b/Lib/test/test_peg_generator/__init__.py
@@ -1,7 +1,15 @@
-import os
-
+import os.path
+import unittest
+from test import support
 from test.support import load_package_tests
 
+
+if support.check_sanitizer(address=True, memory=True):
+    # bpo-46633: Skip the test because it is too slow when Python is built
+    # with ASAN/MSAN: between 5 and 20 minutes on GitHub Actions.
+    raise unittest.SkipTest("test too slow on ASAN/MSAN build")
+
+
 # Load all tests in package
 def load_tests(*args):
     return load_package_tests(os.path.dirname(__file__), *args)
diff --git a/Lib/test/test_tix.py b/Lib/test/test_tix.py
index e6ea3d07444ce7..9dbf9b240b4fc2 100644
--- a/Lib/test/test_tix.py
+++ b/Lib/test/test_tix.py
@@ -1,7 +1,12 @@
 import unittest
 from test import support
+from test.support import check_sanitizer
 import sys
 
+if check_sanitizer(address=True, memory=True):
+    raise unittest.SkipTest("Tests involvin libX11 can SEGFAULT on ASAN/MSAN builds")
+
+
 # Skip this test if the _tkinter module wasn't built.
 _tkinter = support.import_module('_tkinter')
 
diff --git a/Lib/test/test_tk.py b/Lib/test/test_tk.py
index d45acbfc6e1a81..577ed133ee9076 100644
--- a/Lib/test/test_tk.py
+++ b/Lib/test/test_tk.py
@@ -1,4 +1,10 @@
+import unittest
 from test import support
+from test.support import check_sanitizer
+
+if check_sanitizer(address=True, memory=True):
+    raise unittest.SkipTest("Tests involvin libX11 can SEGFAULT on ASAN/MSAN builds")
+
 # Skip test if _tkinter wasn't built.
 support.import_module('_tkinter')
 
diff --git a/Lib/test/test_tools/__init__.py b/Lib/test/test_tools/__init__.py
index eb9acad677d58a..3b5c5b2df5f1df 100644
--- a/Lib/test/test_tools/__init__.py
+++ b/Lib/test/test_tools/__init__.py
@@ -5,6 +5,13 @@
 import unittest
 from test import support
 
+
+if support.check_sanitizer(address=True, memory=True):
+    # bpo-46633: Skip the test because it is too slow when Python is built
+    # with ASAN/MSAN: between 5 and 20 minutes on GitHub Actions.
+    raise unittest.SkipTest("test too slow on ASAN/MSAN build")
+
+
 basepath = os.path.normpath(
         os.path.dirname(                 # <src/install dir>
             os.path.dirname(                # Lib
diff --git a/Lib/test/test_ttk_guionly.py b/Lib/test/test_ttk_guionly.py
index 0b57d5a0d6c25e..e62636637c35f8 100644
--- a/Lib/test/test_ttk_guionly.py
+++ b/Lib/test/test_ttk_guionly.py
@@ -1,5 +1,9 @@
 import unittest
 from test import support
+from test.support import check_sanitizer
+
+if check_sanitizer(address=True, memory=True):
+    raise unittest.SkipTest("Tests involvin libX11 can SEGFAULT on ASAN/MSAN builds")
 
 # Skip this test if _tkinter wasn't built.
 support.import_module('_tkinter')