[BUG] Caught signal 11 (Segmentation fault: address not mapped to object at address 0x55b0b7f836b3)

[manzo1991]

Describe the bug
A clear and concise description of what the bug is.

Got this error while running a model

Setting parameter time_limit to 6.010000e+02
Solving a problem with 650 constraints 2750 variables (2600 integers) and 21250 nonzeros
Objective offset 0.000000 scaling_factor 1.000000
After trivial presolve updated 650 constraints 2750 variables. Objective offset 0.000000
Running presolve!
Solving LP root relaxation
Scaling matrix. Maximum column norm 2.282911e+00
Dual Simplex Phase 1
Dual feasible solution found.
Dual Simplex Phase 2
Iter Objective Num Inf. Sum Inf. Perturb Time
1 +0.0000000000000000e+00 249 1.30286249e+02 0.00e+00 0.18

Root relaxation solution found in 995 iterations and 0.29s
Root relaxation objective +0.00000000e+00

Strong branching using 2 threads and 54 fractional variables
| Explored | Unexplored | Objective | Bound | Depth | Iter/Node | Gap | Time
0 1 +inf +0.000000e+00 1 0.0e+00 - 0.40
2000 1113 +inf +0.000000e+00 101 7.5e+00 - 1.74
3000 1843 +inf +0.000000e+00 44 8.3e+00 - 4.15
4000 2551 +inf +0.000000e+00 69 9.4e+00 - 9.79
Encountered LP status 5. This indicates a numerical issue.
Explored 4617 nodes in 12.69s.
Absolute Gap inf Objective inf Lower Bound 0.0000000000000000e+00
[C11-Y2GLM726B6H:76899:0:77147] Caught signal 11 (Segmentation fault: address not mapped to object at address 0x55b0b7f836b3)
==== backtrace (tid: 77147) ====
0 /home/albertomanzini/.local/lib/python3.12/site-packages/libucx/lib/libucs.so(ucs_handle_error+0x294) [0x7f4dd0ecc2f4]
1 /home/albertomanzini/.local/lib/python3.12/site-packages/libucx/lib/libucs.so(+0x324af) [0x7f4dd0ecc4af]
2 /home/albertomanzini/.local/lib/python3.12/site-packages/libucx/lib/libucs.so(+0x32776) [0x7f4dd0ecc776]
3 /lib/x86_64-linux-gnu/libc.so.6(+0x45330) [0x7f4e72caa330]
4 /home/albertomanzini/.local/lib/python3.12/site-packages/libcuopt/lib64/libcuopt.so(ZN5cuopt18linear_programming12dual_simplex23uncrush_primal_solutionIidEEvRKNS1_14user_problem_tIT_T0_EERKNS1_12lp_problem_tIS4_S5_EERKSt6vectorIS5_SaIS5_EERSF+0x11) [0x7f4d261a9071]
5 /home/albertomanzini/.local/lib/python3.12/site-packages/libcuopt/lib64/libcuopt.so(_ZN5cuopt18linear_programming12dual_simplex18branch_and_bound_tIidE5solveERNS1_14mip_solution_tIidEE+0x18d7) [0x7f4d26191be7]
6 /home/albertomanzini/.local/lib/python3.12/site-packages/libcuopt/lib64/libcuopt.so(_ZNSt17_Function_handlerIFSt10unique_ptrINSt13__future_base12_Result_baseENS2_8_DeleterEEvENS1_12_Task_setterIS0_INS1_7_ResultIN5cuopt18linear_programming12dual_simplex12mip_status_tEEES3_ENSt6thread8_InvokerISt5tupleIJMNSA_18branch_and_bound_tIidEEFSB_RNSA_14mip_solution_tIidEEEPSI_St17reference_wrapperISK_EEEEESB_EEE9_M_invokeERKSt9_Any_data+0x36) [0x7f4d25cb8346]
7 /home/albertomanzini/.local/lib/python3.12/site-packages/libcuopt/lib64/libcuopt.so(_ZNSt13__future_base13_State_baseV29_M_do_setEPSt8functionIFSt10unique_ptrINS_12_Result_baseENS3_8_DeleterEEvEEPb+0x1b) [0x7f4d25cb840b]
8 /lib/x86_64-linux-gnu/libc.so.6(+0xa1ed3) [0x7f4e72d06ed3]
9 /home/albertomanzini/.local/lib/python3.12/site-packages/libcuopt/lib64/libcuopt.so(_ZNSt13__future_base17_Async_state_implINSt6thread8_InvokerISt5tupleIJMN5cuopt18linear_programming12dual_simplex18branch_and_bound_tIidEEFNS6_12mip_status_tERNS6_14mip_solution_tIidEEEPS8_St17reference_wrapperISB_EEEEES9_E6_M_runEv+0xfb) [0x7f4d25cb948b]
10 /home/albertomanzini/miniconda3/envs/nvidia/bin/../lib/libstdc++.so.6(+0xd8198) [0x7f4e703e3198]
11 /lib/x86_64-linux-gnu/libc.so.6(+0x9caa4) [0x7f4e72d01aa4]
12 /lib/x86_64-linux-gnu/libc.so.6(+0x129c6c) [0x7f4e72d8ec6c]

Steps/Code to reproduce bug
Follow this guide http://matthewrocklin.com/blog/work/2018/02/28/minimal-bug-reports to craft a minimal bug report. This helps us reproduce the issue you're having and resolve the issue more quickly.

See attached code

bug_report.py

Expected behavior
A clear and concise description of what you expected to happen.

Environment details (please complete the following information):

• Environment location: [Bare-metal, Docker, Cloud(specify cloud provider)]: bare metal on Ubuntu subsystem, CUDA version 12
• Method of cuOpt install: [conda, Docker, or from source]: conda
  • If method of install is [Docker], provide docker pull & docker run commands used

Additional context
Add any other context about the problem here.

[rgsl888prabhu]

@manzo1991 Thank you for reporting the issue,

Can you please shar following details

• on cuOpt version and env where it failed?
• details on GPU used?
• A repro script with data if possible?

[rgsl888prabhu]

@rg20 Have you see this issue before, has this been addressed in any of our recent PRs?

[manzo1991]

@rgsl888prabhu Data are generated in code attached in previous message.

GPU info:
NVIDIA-SMI 525.116 Driver Version: 528.96 CUDA Version: 12.0
NVIDIA RTX A500 Laptop GPU

below the pip freeze of the environement

absl-py==2.3.1
annotated-types==0.7.0
anyio==4.11.0
Brotli @ file:///home/conda/feedstock_root/build_artifacts/brotli-split_1756599151967/work
cachetools==6.1.0
certifi @ file:///home/conda/feedstock_root/build_artifacts/certifi_1754231422783/work/certifi
cffi @ file:///home/conda/feedstock_root/build_artifacts/cffi_1725560558132/work
charset-normalizer @ file:///home/conda/feedstock_root/build_artifacts/charset-normalizer_1754767332901/work
click==8.2.1
cloudpickle==3.1.1
cuda-bindings==12.9.2
cuda-pathfinder==1.1.0
cuda-python==12.9.2
cudf-cu12==25.8.0
cuopt-cu12==25.8.0
cuopt_mps_parser==25.8.0
cuopt_server-cu12==25.8.0
cuopt_sh_client @ file:///tmp/conda-bld-output/bld/rattler-build_cuopt-sh-client/work/python/cuopt_self_hosted
cupy-cuda12x==13.6.0
cuvs-cu12==25.8.0
dask==2025.7.0
dask-cuda==25.8.0
distributed==2025.7.0
distributed-ucxx-cu12==0.45.1
fastapi==0.116.1
fastrlock==0.8.3
fsspec==2025.7.0
h11==0.16.0
h2 @ file:///home/conda/feedstock_root/build_artifacts/bld/rattler-build_h2_1756364871/work
hpack @ file:///home/conda/feedstock_root/build_artifacts/hpack_1737618293087/work
httpcore==1.0.9
httpx==0.28.1
hyperframe @ file:///home/conda/feedstock_root/build_artifacts/hyperframe_1737618333194/work
idna @ file:///home/conda/feedstock_root/build_artifacts/idna_1733211830134/work
immutabledict==4.2.1
Jinja2==3.1.6
jsonargparse==4.41.0
jsonref==1.1.0
libcudf-cu12==25.8.0
libcuopt-cu12==25.8.0
libcuvs-cu12==25.8.0
libkvikio-cu12==25.8.0
libraft-cu12==25.8.0
librmm-cu12==25.8.0
libucx-cu12==1.18.1
libucxx-cu12==0.45.1
llvmlite==0.44.0
locket==1.0.0
markdown-it-py==4.0.0
MarkupSafe==3.0.3
mdurl==0.1.2
msgpack @ file:///home/conda/feedstock_root/build_artifacts/msgpack-python_1725975016068/work
msgpack-numpy==0.4.8
numba==0.61.2
numba-cuda==0.14.0
numpy==2.2.6
nvidia-cublas-cu12==12.9.1.4
nvidia-cuda-nvcc-cu12==12.9.86
nvidia-cuda-nvrtc-cu12==12.9.86
nvidia-cuda-runtime-cu12==12.9.79
nvidia-curand-cu12==10.3.10.19
nvidia-cusolver-cu12==11.7.5.82
nvidia-cusparse-cu12==12.5.10.65
nvidia-ml-py==12.575.51
nvidia-nccl-cu12==2.27.7
nvidia-nvjitlink-cu12==12.9.86
nvidia-nvtx-cu12==12.9.79
nvtx==0.2.13
ortools==9.14.6206
packaging==25.0
pandas==2.3.2
partd==1.4.2
protobuf==6.31.1
psutil==5.9.6
pyarrow==19.0.1
pycparser @ file:///home/conda/feedstock_root/build_artifacts/bld/rattler-build_pycparser_1733195786/work
pydantic==2.11.7
pydantic_core==2.33.2
Pygments==2.19.2
pylibcudf-cu12==25.8.0
pylibraft-cu12==25.8.0
pynvjitlink-cu12==0.7.0
pynvml==12.0.0
PySocks @ file:///home/conda/feedstock_root/build_artifacts/pysocks_1733217236728/work
python-dateutil==2.9.0.post0
pytz==2025.2
PyYAML==6.0.3
raft-dask-cu12==25.8.0
rapids-dask-dependency==25.8.0
rapids-logger==0.1.1
requests @ file:///home/conda/feedstock_root/build_artifacts/requests_1755614211359/work
rich==14.1.0
rmm-cu12==25.8.0
setuptools==78.1.1
six==1.17.0
sniffio==1.3.1
sortedcontainers==2.4.0
starlette==0.47.2
tblib==3.1.0
toolz==1.0.0
tornado==6.5.2
typing-inspection==0.4.1
typing_extensions==4.15.0
tzdata==2025.2
ucx-py-cu12==0.45.0
ucxx-cu12==0.45.1
urllib3 @ file:///home/conda/feedstock_root/build_artifacts/urllib3_1750271362675/work
uvicorn==0.34.3
wheel==0.45.1
zict==3.0.0
zstandard==0.25.0

[rgsl888prabhu]

Thank you @manzo1991 will test it and follow-up on the issue

[manzo1991]

Hi @rgsl888prabhu , any news?

[rgsl888prabhu]

Hi @manzo1991, we have made a release yesterday with several fixes pertaining to segfaults, would you mind giving it a try with 25.10 version ?

[manzo1991]

@rgsl888prabhu seems is not working with new version of cuopt (25.10), here the log from the script attached in my first message:

Setting parameter time_limit to 6.010000e+02
cuOpt version: 25.10.0, git hash: 99e549c, host arch: x86_64, device archs: 70-real,75-real,80-real,86-real,90a-real,100f-real,120a-real,120
CPU: 13th Gen Intel(R) Core(TM) i7-13800H, threads (physical/logical): 10/20, RAM: 0.15 GiB
CUDA 12.9, device: NVIDIA RTX A500 Laptop GPU (ID 0), VRAM: 4.00 GiB
CUDA device UUID: ffffffddffffffd0ffffffe3ffffffcb-7d4

Solving a problem with 650 constraints, 2750 variables (2750 integers), and 21250 nonzeros
Problem scaling:
Objective coefficents range:          [1e+00, 1e+00]
Constraint matrix coefficients range: [1e+00, 1e+03]
Constraint rhs / bounds range:        [0e+00, 1e+03]
Variable bounds range:                [0e+00, 2e+03]

Original problem: 650 constraints, 2750 variables, 21250 nonzeros
Calling Papilo presolver
Presolve status: reduced the problem
Presolve removed: 150 constraints, 50 variables, 350 nonzeros
Presolved problem: 500 constraints, 2700 variables, 20900 nonzeros
Papilo presolve time: 0.193447
Objective offset -nan scaling_factor 1.000000
Running presolve!
After trivial presolve: 500 constraints, 2700 variables, objective offset -nan.
Using 19 CPU threads for B&B
Solving LP root relaxation
Scaling matrix. Maximum column norm 1.717324e+00
Dual Simplex Phase 1
Dual infeasible
MIP Unbounded

Looks like the model is infeasible, but I'm sure it is feasible because I'm solving the same model with another solver...