scip crashes with heurExecAlns(SCIP *, SCIP_HEUR *, SCIP_HEURTIMING, unsigned int, SCIP_RESULT *): Assertion `FALSE' failed #139
Description
For seed.lp.txt, scip crashes with the following parameters:
numerics/feastol = 1e-9
lp/scaling = 0
numerics/epsilon = 1e-9
numerics/sumepsilon = 1e-9
Actually, numerics/epsilon and numerics/sumepsilon are not necessary to trigger the crash, I just added them to follow your instructions of holding numerics/epsilon <= numerics/sumepsilon <= numerics/feastol.
The trace:
scip -s scip_options.set -f seed.lp
SCIP version 10.0.0 [precision: 8 byte] [memory: block] [mode: debug] [LP solver: SoPlex 8.0.0] [GitHash: ec8ae324dd]
Copyright (c) 2002-2025 Zuse Institute Berlin (ZIB)
External libraries:
SoPlex 8.0.0 Linear programming solver developed at Zuse Institute Berlin (soplex.zib.de) [GitHash: 85549f2c]
CppAD 20180000.0 Algorithmic Differentiation of C++ algorithms developed by B. Bell (github.com/coin-or/CppAD)
ZLIB 1.2.11 General purpose compression library by J. Gailly and M. Adler (zlib.net)
TinyCThread 1.2 small portable implementation of the C11 threads API (tinycthread.github.io)
GMP 6.2.0 GNU Multiple Precision Arithmetic Library developed by T. Granlund (gmplib.org)
AMPL/MP 4.0.0 AMPL .nl file reader library (github.com/ampl/mp)
Nauty 2.8.8 Computing Graph Automorphism Groups by Brendan D. McKay (users.cecs.anu.edu.au/~bdm/nauty)
sassy 2.0 Symmetry preprocessor by Markus Anders (github.com/markusa4/sassy)
reading user parameter file <scip_options.set>
read problem <seed.lp>
============
original problem has 17 variables (0 bin, 10 int, 7 cont) and 129 constraints
solve problem
=============
presolving:
(0.1s) symmetry computation started: requiring (bin +, int +, cont +), (fixed: bin -, int -, cont -)
(0.1s) no symmetry present (symcode time: 0.00)
presolving (1 rounds: 1 fast, 1 medium, 1 exhaustive):
0 deleted vars, 0 deleted constraints, 0 added constraints, 0 tightened bounds, 0 added holes, 0 changed sides, 0 changed coefficients
0 implications, 0 cliques
presolved problem has 17 variables (0 bin, 10 int, 7 cont) and 129 constraints
presolved problem has 0 implied integral variables (0 bin, 0 int, 0 cont)
129 constraints of type <linear>
Presolving Time: 0.14
time | node | left |LP iter|LP it/n|mem/heur|mdpt |vars |cons |rows |cuts |sepa|confs|strbr| dualbound | primalbound | gap | compl.
0.2s| 1 | 0 | 45 | - | 5960k | 0 | 17 | 130 | 129 | 0 | 0 | 1 | 0 |-6.119326e+04 | -- | Inf | unknown
0.5s| 1 | 0 | 46 | - | 6023k | 0 | 17 | 130 | 130 | 1 | 1 | 1 | 0 |-6.118965e+04 | -- | Inf | unknown
0.8s| 1 | 0 | 47 | - | 6147k | 0 | 17 | 130 | 131 | 2 | 2 | 1 | 0 |-6.118747e+04 | -- | Inf | unknown
1.1s| 1 | 0 | 48 | - | 6161k | 0 | 17 | 130 | 132 | 3 | 3 | 1 | 0 |-6.118598e+04 | -- | Inf | unknown
1.3s| 1 | 0 | 49 | - | 6175k | 0 | 17 | 130 | 133 | 4 | 4 | 1 | 0 |-6.118421e+04 | -- | Inf | unknown
1.6s| 1 | 0 | 50 | - | 6189k | 0 | 17 | 130 | 134 | 5 | 5 | 1 | 0 |-6.118331e+04 | -- | Inf | unknown
1.8s| 1 | 0 | 52 | - | 6337k | 0 | 17 | 130 | 135 | 6 | 6 | 1 | 0 |-6.118183e+04 | -- | Inf | unknown
1.9s| 1 | 0 | 54 | - | 6455k | 0 | 17 | 130 | 136 | 7 | 7 | 1 | 0 |-6.118110e+04 | -- | Inf | unknown
2.1s| 1 | 0 | 55 | - | 6532k | 0 | 17 | 130 | 137 | 8 | 8 | 1 | 0 |-6.118084e+04 | -- | Inf | unknown
2.3s| 1 | 0 | 57 | - | 6546k | 0 | 17 | 130 | 138 | 9 | 9 | 1 | 0 |-6.117986e+04 | -- | Inf | unknown
2.5s| 1 | 0 | 59 | - | 6561k | 0 | 17 | 130 | 140 | 11 | 10 | 1 | 0 |-6.117920e+04 | -- | Inf | unknown
2.7s| 1 | 0 | 60 | - | 6576k | 0 | 17 | 130 | 141 | 12 | 11 | 1 | 0 |-6.117911e+04 | -- | Inf | unknown
Cannot set feasibility tolerance to small value 1e-12 without GMP - using 1e-10.
[solve.c:4198] ERROR: (node 1) unresolved numerical troubles in LP 4 cannot be dealt with
[solve.c:4492] ERROR: Error <-6> in function call
[solve.c:5315] ERROR: Error <-6> in function call
[scip_solve.c:2798] ERROR: Error <-6> in function call
[heur_alns.c:2640] ERROR: Error <-6> in function call
scip: /home/x27zhou/scip/scip/src/scip/heur_alns.c:2640: SCIP_RETCODE heurExecAlns(SCIP *, SCIP_HEUR *, SCIP_HEURTIMING, unsigned int, SCIP_RESULT *): Assertion `FALSE' failed.
Aborted (core dumped)