[SCIP] Bliss causing free() crashes

[Alex Meiburg]

Hi all,

I build and installed SCIP through cmake with SYM=bliss, and I installed
bliss libbliss-dev from Ubunutu's package repository, which uses version
0.73. The building found Bliss without any issue. After playing around it
seemed that actually get it to use this featuer, I needed to "set misc
usesymmetry 1", and then it crashes during presolve.

To be precise, my full sequence of actions is:
$ scip
SCIP> read problem_16.lp
SCIP> set misc usesymmetry 1
SCIP> presolve

and then it gives this output:

LP Solver <SoPlex 4.0.1>: barrier convergence tolerance cannot be set --
tolerance of SCIP and LP solver may differ
LP Solver <SoPlex 4.0.1>: fastmip setting not available -- SCIP parameter
has no effect
LP Solver <SoPlex 4.0.1>: number of threads settings not available -- SCIP
parameter has no effect
transformed problem has 1540 variables (0 bin, 1540 int, 0 impl, 0 cont)
and 31462 constraints
  31462 constraints of type <linear>

original problem has 92905 active (0.191749%) nonzeros and 92905
(0.191749%) check nonzeros

presolving:
(round 1, fast)       505 del vars, 3630 del conss, 0 add conss, 3585 chg
bounds, 0 chg sides, 0 chg coeffs, 0 upgd conss, 0 impls, 0 clqs
(round 2, fast)       910 del vars, 25608 del conss, 0 add conss, 3990 chg
bounds, 0 chg sides, 0 chg coeffs, 0 upgd conss, 0 impls, 0 clqs
(round 3, fast)       910 del vars, 28222 del conss, 0 add conss, 3990 chg
bounds, 0 chg sides, 0 chg coeffs, 0 upgd conss, 0 impls, 0 clqs
(round 4, exhaustive) 910 del vars, 28267 del conss, 0 add conss, 3990 chg
bounds, 0 chg sides, 0 chg coeffs, 0 upgd conss, 0 impls, 0 clqs
(round 5, exhaustive) 910 del vars, 28267 del conss, 0 add conss, 3990 chg
bounds, 0 chg sides, 0 chg coeffs, 3150 upgd conss, 0 impls, 0 clqs
   (0.2s) probing: 51/630 (8.1%) - 0 fixings, 0 aggregations, 0
implications, 0 bound changes
   (0.2s) probing aborted: 50/50 successive totally useless probings
   (0.2s) symmetry computation started: requiring (bin +, int +, cont +),
(fixed: bin -, int -, cont -)
free(): invalid pointer
Aborted (core dumped)

Is something wrong with my bliss installation? Am I misusing the
misc/symmetry settings? When I tried building bliss myself, it wasn't
creating a .so (only .a), so is there a build script that handles it? Once
I have it working, I would like to compile the SCIP-SDP plugin in too,
which means I'd like to not use a pre-built version. Thank you all!

-- Alexander Meiburg
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