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HiGHS crashes with `--presolve on` and `mip_rel_gap=0`

Open zxt5 opened this issue 10 months ago • 1 comments

HiGHS crashes on seed.mps.txt when --presolve on and mip_rel_gap is set to 0 at the same time (set mip_abs_gap=0 would not trigger the crash).

Not sure if this is a duplicate of #2174, as this one is different by crashing on assertion ub_consistent

root@b9f8d0525121:/tmp/fuzz-mip# highs --model_file seed.mps --presolve on --options_file=highs_options.txt
Running HiGHS 1.9.0 (git hash: 28ed9f7b4): Copyright (c) 2025 HiGHS under MIT licence terms
Set option presolve to "on"
Set option log_file to "HiGHS.log"
Set option mip_rel_gap to 0
MIP  seed has 80 rows; 6 cols; 480 nonzeros; 5 integer variables
Coefficient ranges:
  Matrix [3e-02, 2e+01]
  Cost   [5e+01, 1e+02]
  Bound  [2e+02, 2e+02]
  RHS    [3e+00, 1e+02]
Presolving model
80 rows, 6 cols, 480 nonzeros  0.001034s
80 rows, 6 cols, 480 nonzeros  0.002426s

Solving MIP model with:
   80 rows
   6 cols (0 binary, 5 integer, 0 implied int., 1 continuous)
   480 nonzeros

Src: B => Branching; C => Central rounding; F => Feasibility pump; H => Heuristic; L => Sub-MIP;
     P => Empty MIP; R => Randomized rounding; S => Solve LP; T => Evaluate node; U => Unbounded;
     z => Trivial zero; l => Trivial lower; u => Trivial upper; p => Trivial point

        Nodes      |    B&B Tree     |            Objective Bounds              |  Dynamic Constraints |       Work
Src  Proc. InQueue |  Leaves   Expl. | BestBound       BestSol              Gap |   Cuts   InLp Confl. | LpIters     Time

         0       0         0   0.00%   -86592          inf                  inf        0      0      0         0     0.0s
         0       0         0   0.00%   -46402.125996   inf                  inf        0      0      2        10     0.0s
 R       0       0         0   0.00%   -46399.482043   -46390.174938      0.02%       14      2      4        12     0.0s
 H       0       0         0   0.00%   -46399.482043   -46390.174938      0.02%       14      2     12        12     0.0s

40.0% inactive integer columns, restarting
Model after restart has 67 rows, 4 cols (0 bin., 3 int., 0 impl., 1 cont.), and 268 nonzeros

         0       0         0   0.00%   -46399.291654   -46390.174938      0.02%        1      0      0        30     0.1s
         0       0         0   0.00%   -46399.291654   -46390.174938      0.02%        1      1      0        36     0.1s
 L       0       0         0   0.00%   -46394.837725   -46390.17494       0.01%       36      3     46        67     0.1s

Restarting search from the root node
highs: /tmp/HiGHS/src/mip/HighsMipSolverData.cpp:2620: void HighsMipSolverData::updatePrimalDualIntegral(double, double, double, double, bool, bool): Assertion `ub_consistent' failed.
Aborted (core dumped)

zxt5 avatar Feb 12 '25 09:02 zxt5

This is a duplicate of #2174

jajhall avatar Feb 12 '25 09:02 jajhall