BUG: Running test suite in parallel with AddressSanitizer results in errors and crashes #29890

Describe the issue:

When running the NumPy test suite with pytest-run-parallel and AddressSanitizer, some tests result in ASan errors and a few even result in fatal terminations that crash the entire terminal.

Affected tests

• numpy/_core/tests/test_arrayprint.py::test_multithreaded_array_printing
  • Fatal termination, no output or specific error
• numpy/_core/tests/test_shape_base.py::TestConcatenate::test_huge_list_error
  • Fatal termination, no output or specific error
• numpy/_core/tests/test_array_coercion.py::TestArrayLikes::test_too_large_array_error_paths
  • No crash, failed to allocate bytes ASan error
• numpy/_core/tests/test_multiarray.py::TestCreation::test_malloc_fails
  • No crash, failed to allocate bytes ASan error
• numpy/lib/tests/test_io.py::TestFromTxt::test_utf8_file_nodtype_unicode
  • Fatal termination after printing heap-use-after-free on address ASan error

Steps to reproduce

• Use Python 3.14t-dev with AddressSanitizer enabled.
  • Steps on how to do this can be found here or in this PR for the docs.
  • Currently using these ASAN options export ASAN_OPTIONS=detect_leaks=0:symbolize=1:strict_init_order=true:allocator_may_return_null=1:halt_on_error=0
• Build NumPy using clang, AddressSanitizer and without openBLAS
  • spin build --clean -- -Db_sanitize=address -Dbuildtype=debugoptimized -Dallow-noblas=true
• Run test suite under pytest-run-parallel
  • spin test -- --parallel-threads=auto -sv

Reproduce the code example:

N/A

Error message:

============
numpy/_core/tests/test_arrayprint.py::test_multithreaded_array_printing
============
No specific error output, just prints "Terminated" after test


============
numpy/_core/tests/test_shape_base.py::TestConcatenate::test_huge_list_error
============
No specific error output, just prints "Terminated" after test


============
numpy/_core/tests/test_array_coercion.py::TestArrayLikes::test_too_large_array_error_paths
============
numpy/_core/tests/test_array_coercion.py::TestArrayLikes::test_too_large_array_error_paths ==12708==WARNING: AddressSanitizer failed to allocate 0x4000000000000000 bytes
[... prints multiple times]
==12708==WARNING: AddressSanitizer failed to allocate 0x4000000000000000 bytes
PARALLEL PASSED


============
numpy/_core/tests/test_multiarray.py::TestCreation::test_malloc_fails
============
numpy/_core/tests/test_multiarray.py::TestCreation::test_malloc_fails ==123475==WARNING: AddressSanitizer failed to allocate 0x7fffffffffffffff bytes
==123475==WARNING: AddressSanitizer failed to allocate 0x7fffffffffffffff bytes
[... prints multiple times]
==123475==WARNING: AddressSanitizer failed to allocate 0x7fffffffffffffff bytes
PARALLEL PASSED


============
numpy/lib/tests/test_io.py::TestFromTxt::test_utf8_file_nodtype_unicode
============
Full traceback for test_io.py file https://gist.github.com/bwhitt7/29d89710dc46a4feb52b8045c0c8bd7c

Python and NumPy Versions:

NumPy: 2.4.0.dev0+git20251003.da5c632
Python: 3.14.0rc3+ free-threading build (heads/3.14:460ad1aa1ba, Sep 22 2025, 23:51:20) [Clang 18.1.3 (1ubuntu1)]

Runtime Environment:

[{'numpy_version': '2.4.0.dev0+git20251003.da5c632',
  'python': '3.14.0rc3+ free-threading build (heads/3.14:460ad1aa1ba, Sep 22 '
            '2025, 23:51:20) [Clang 18.1.3 (1ubuntu1)]',
  'uname': uname_result(system='Linux', node='SPACE', release='6.6.87.2-microsoft-standard-WSL2', version='#1 SMP PREEMPT_DYNAMIC Thu Jun  5 18:30:46 UTC 2025', machine='x86_64')},
 {'simd_extensions': {'baseline': ['SSE', 'SSE2', 'SSE3'],
                      'found': ['SSSE3',
                                'SSE41',
                                'POPCNT',
                                'SSE42',
                                'AVX',
                                'F16C',
                                'FMA3',
                                'AVX2'],
                      'not_found': ['AVX512F',
                                    'AVX512CD',
                                    'AVX512_KNL',
                                    'AVX512_SKX',
                                    'AVX512_CLX',
                                    'AVX512_CNL',
                                    'AVX512_ICL']}},
 {'architecture': 'Haswell',
  'filepath': '/usr/lib/x86_64-linux-gnu/openblas-pthread/libopenblasp-r0.3.26.so',
  'internal_api': 'openblas',
  'num_threads': 24,
  'prefix': 'libopenblas',
  'threading_layer': 'pthreads',
  'user_api': 'blas',
  'version': '0.3.26'}]

Context for the issue:

ASan helps detect memory errors. Looks like running these tests in threads causes some sort of memory issue, so taking a look at these would help improve NumPy's thread safety.