Notes:

* test.support has check_sanitizer() function. Tests using it:

  * test_crypt
  * test_idle
  * test_tix
  * test_tk
  * test_ttk_guionly


* test_decimal also checks for memory sanitizer and skip some tests if it's present:

MEMORY_SANITIZER = (
    '-fsanitize=memory' in _cflags or
    '--with-memory-sanitizer' in _config_args
)   

* test_faulthandler suppress crash report, similir to support.SuppressCrashReport, directly in the C code used by tests: faulthandler_suppress_crash_report() function.

* Objects/obmalloc.c checks "#if __has_feature(address_sanitizer)": is ASAN enabled?

* GitHub Action config: .github/workflows/build.yml. Skipped tests:

  * test___all__
  * test_concurrent_futures
  * test_multiprocessing_fork
  * test_multiprocessing_forkserver
  * test_multiprocessing_spawn
  * test_peg_generator
  * test_tools

Comment:
---
# Skip test_tools test_peg_generator test_concurrent_futures because
# there are too slow: between 5 and 20 minutes on this CI.
#
# Skip multiprocessing and concurrent.futures tests which are affected by
# bpo-45200 bug: libasan dead lock in pthread_create().
#
# test___all__ is skipped because importing some modules directly can trigger
# known problems with ASAN (like tk or crypt).
---

* Buildbot configuration: UnixAsanBuild class of master/custom/factories.py. Options:

  ASAN_OPTIONS='detect_leaks=0:allocator_may_return_null=1:handle_segv=0'

With the comment:
---
# See https://bugs.python.org/issue42985 for more context on why
# SIGSEGV is ignored on purpose.
---

  Skipped tests:
  
  * test_ctypes
  * test_capi
  * test_crypt
  * test_decimal
  * test_faulthandler
  * test_interpreters

With the comment:
---
# These tests are currently raising false positives or are interfering with the ASAN mechanism,
# so we need to skip them unfortunately.
---