NVIDIA / NVIDIA/cuopt

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

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Since Dec 1, 2025.

bug
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Description

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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
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bug_report.py

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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

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