[Bug-glpk] Assertion failed: spx->p != 0; file glpspx2.c; line 668

[Oleg Eterevsky]

Hello!

glpsol crushed on the attached input MPS-file with an internal assert.
The complete output:

address@hidden bug]$ glpsol prob3.mps
lpx_read_mps: reading problem data from `prob3.mps'...
lpx_read_mps: problem elsom_lp
lpx_read_mps: 1986 rows, 3280 columns, 9003 non-zeros
lpx_read_mps: 28 integer columns, none of which are binary
lpx_read_mps: 13862 cards were read
lpx_simplex: original LP has 1986 rows, 3280 columns, 9003 non-zeros
lpx_simplex: presolved LP has 1950 rows, 2814 columns, 6243 non-zeros
lpx_adv_basis: size of triangular part = 1926
      0:   objval =   0.000000000e+00   infeas =   1.000000000e+00 (10)
    116:   objval =   7.646381712e+08   infeas =   3.424473137e-24 (4)
*   116:   objval =   7.646381712e+08   infeas =   6.225692162e-20 (4)
*   200:   objval =   6.174001496e+08   infeas =   2.313458737e-20 (0)
*   251:   objval =   5.968232068e+08   infeas =   1.776356839e-14 (0)
OPTIMAL SOLUTION FOUND
Integer optimization begins...
+   251: mip =     not found yet >=              -inf        (1; 0)
spx_simplex: numerical instability (dual simplex)
+   629: mip =   1.235198649e+11 >=   5.968232068e+08  99.5% (16; 0)
spx_simplex: numerical instability (dual simplex)
spx_simplex: numerical instability (dual simplex)
spx_simplex: numerical instability (dual simplex)
spx_simplex: numerical instability (dual simplex)
spx_simplex: numerical instability (dual simplex)
spx_simplex: numerical instability (dual simplex)
spx_simplex: numerical instability (dual simplex)
+  3100: mip =   1.188070884e+11 >=   5.968232068e+08  99.5% (52; 11)
+  3226: mip =   8.120514686e+10 >=   5.968232068e+08  99.3% (56; 16)
spx_simplex: numerical instability (dual simplex)
spx_simplex: numerical instability (primal simplex, phase I)
spx_simplex: numerical instability (dual simplex)
Assertion failed: spx->p != 0; file glpspx2.c; line 668

I've compiled GLPK with the following flags: "-O3 -march=pentium4
-ffast-math" with gcc version 3.3.4 20040817 (ALT Linux, build
3.3.4-alt1) on pentium4 with 2Gb of RAM.

--
Best wishes,
Oleg Eterevsky.

prob3.mps.bz2
Description: BZip2 compressed data