Bug report
Bug description:
The program that triggers the crash:
import numpy
for _ in range(200):
numpy.prod(2, dtype=numpy.intp)Reproducer at https://github.com/lucascolley/cpython-np-prod-repro. This produces the SEGV on CPython main branch, but passes on the 3.15 branch.
❯ export BUILD_EDITABLE_PYTHON=false
❯ pixi run repro
✨ Pixi task (repro): python repro.py
Python: 3.16.0a0 (heads/master-dirty:d8a1072491, Sep 16 2026, 22:19:03) [Clang 21.1.8 ]
AddressSanitizer:DEADLYSIGNAL
=================================================================
==54023==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x00010639c214 bp 0x00016afdf230 sp 0x00016afdf1d0 T0)
==54023==The signal is caused by a WRITE memory access.
==54023==HINT: address points to the zero page.
#0 0x00010639c214 in _PyGCHead_SET_NEXT pycore_gc.h:151
#1 0x00010639c214 in _PyObject_GC_UNTRACK pycore_gc.h:264
#2 0x00010639c214 in type_dealloc typeobject.c:6898
#3 0x000106338e40 in _Py_Dealloc object.c:3333
#4 0x00010e880a34 in PyUFunc_GenericReduction+0x119c (_multiarray_umath.cpython-316-darwin.so:arm64+0x704a34)
#5 0x000106237858 in _PyVectorcall_Call call.c:273
#6 0x00010652b77c in _PyEval_EvalFrameDefault generated_cases.c.h:2831
#7 0x0001065153bc in _PyEval_EvalFrame pycore_ceval.h:122
#8 0x0001065153bc in _PyEval_Vector ceval.c:2176
#9 0x000106237a78 in _PyObject_VectorcallTstate pycore_call.h:144
#10 0x000106237a78 in PyObject_Vectorcall call.c:327
#11 0x00010e54bd1c in dispatcher_vectorcall+0xc70 (_multiarray_umath.cpython-316-darwin.so:arm64+0x3cfd1c)
#12 0x000106237a78 in _PyObject_VectorcallTstate pycore_call.h:144
#13 0x000106237a78 in PyObject_Vectorcall call.c:327
#14 0x000106515938 in _Py_VectorCall_StackRefSteal ceval.c:728
#15 0x000106529170 in _PyEval_EvalFrameDefault generated_cases.c.h:3686
#16 0x000106514db0 in _PyEval_EvalFrame pycore_ceval.h:122
#17 0x000106514db0 in _PyEval_Vector ceval.c:2176
#18 0x000106514db0 in PyEval_EvalCode ceval.c:681
#19 0x00010665ba10 in run_mod pythonrun.c:1509
#20 0x00010665633c in _PyRun_File pythonrun.c:1332
#21 0x00010665633c in _PyRun_SimpleFile pythonrun.c:544
#22 0x000106655998 in _PyRun_AnyFile pythonrun.c:92
#23 0x0001066bd0b0 in pymain_run_file_obj main.c:478
#24 0x0001066bd0b0 in pymain_run_file main.c:494
#25 0x0001066bbe68 in pymain_run_python main.c:804
#26 0x0001066bbe68 in Py_RunMain main.c:891
#27 0x0001066bc830 in pymain_main main.c:921
#28 0x0001066bc9e0 in Py_BytesMain main.c:945
#29 0x000189febdfc in start+0x1b4c (dyld:arm64e+0x1fdfc)
==54023==Register values:
x[0] = 0x00006190000dde88 x[1] = 0x000000010639c054 x[2] = 0x000000016afde9d0 x[3] = 0x000061600009a870
x[4] = 0x0000000000000218 x[5] = 0x0000000000000218 x[6] = 0x0000000169fe4000 x[7] = 0x0000000000000001
x[8] = 0x00006190000dde80 x[9] = 0x0000000000000000 x[10] = 0x0000000000000000 x[11] = 0x00000fffffffffff
x[12] = 0x0000000000000000 x[13] = 0xffffffffffffffff x[14] = 0x0000000000000000 x[15] = 0x00007fffffffffff
x[16] = 0x0000000000000028 x[17] = 0x0000604000000410 x[18] = 0x0000000000000000 x[19] = 0x00006190000dde90
x[20] = 0x0000604000000438 x[21] = 0x0000000080805980 x[22] = 0x0000008000020000 x[23] = 0x0000000106c42940
x[24] = 0x0000008000020000 x[25] = 0x0000000000000000 x[26] = 0x000000016afdfb20 x[27] = 0x0000000000000000
x[28] = 0x00006110001f42e4 fp = 0x000000016afdf230 lr = 0x000000010639c1d8 sp = 0x000000016afdf1d0
AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV pycore_gc.h:151 in _PyGCHead_SET_NEXT
==54023==ABORTING@ngoldbaum perhaps you can reproduce?
[workspace]
channels = ["https://prefix.dev/conda-forge"]
platforms = ["osx-arm64"]
preview = ["pixi-build"]
requires-pixi = ">=0.74.0"
[tasks]
repro = "python repro.py"
[dependencies]
numpy = {
git = "https://github.com/numpy/numpy",
package = {
host-dependencies = {
python = {
flags = ["asan"],
# passing with 3.15 branch
# branch = "3.15",
# failing with main
branch = "main",
git = "https://github.com/python/cpython",
subdirectory = "Tools/pixi-packages",
},
meson-python = "*",
cython = "*",
},
build = {
backend.name = "pixi-build-python",
config.compilers = ["c", "cxx"],
},
},
}CPython versions tested on:
CPython main branch
Operating systems tested on:
macOS
Bug report
Bug description:
The program that triggers the crash:
Reproducer at https://github.com/lucascolley/cpython-np-prod-repro. This produces the SEGV on CPython main branch, but passes on the 3.15 branch.
@ngoldbaum perhaps you can reproduce?
CPython versions tested on:
CPython main branch
Operating systems tested on:
macOS