Issues

• highspy: chained constraint lhs <= z <= rhs rejected when equal sides are written differently

  ERGO-Code/HiGHS#3602 · Filter by author KeWu5678 opened on Nov 10, 2026

• MIP: Three fixes for slow central rounding and missed time limits

  ERGO-Code/HiGHS#3601 · Filter by author DoumarCharles opened on Nov 10, 2026

• LP presolve declares a feasible 1-row LP infeasible when the rhs lies between primal_feasibility_tolerance and twice it

  ERGO-Code/HiGHS#3600 · Filter by author Kai-Striega opened on Nov 10, 2026

• cmake --install does not install libhighs_extras.so, so HiPO is unavailable in installed builds (v1.15.1)

  ERGO-Code/HiGHS#3599 · Filter by author Ganimed opened on Nov 9, 2026
  1

• MIP: feasibility pump moves the LP away from the rounded point

  ERGO-Code/HiGHS#3597 · Filter by author DoumarCharles opened on Nov 9, 2026
  1

• Presolve: new MIP parity pass (bounds from integer equations modulo 2)

  ERGO-Code/HiGHS#3595 · Filter by author DoumarCharles opened on Nov 9, 2026

• Presolve: skip the clique cover in variable bound aggregation when no row can be merged

  ERGO-Code/HiGHS#3594 · Filter by author DoumarCharles opened on Nov 9, 2026
  

• Presolve: leave clique merging to probing, not enumeration

  ERGO-Code/HiGHS#3593 · Filter by author DoumarCharles opened on Nov 9, 2026
  

• MIP: root separation does not stall when the LP objective does not move

  ERGO-Code/HiGHS#3590 · Filter by author DoumarCharles opened on Nov 9, 2026
  

• Presolve: take dominated-column candidates only from columns in all required rows

  ERGO-Code/HiGHS#3589 · Filter by author DoumarCharles opened on Nov 9, 2026
  

• Presolve: variable bound aggregation breaks the symmetry of fhnw-binpack4-4

  ERGO-Code/HiGHS#3588 · Filter by author DoumarCharles opened on Nov 9, 2026
  2

  

• Presolve: count only possible dominations for the predictive bound analysis limit

  ERGO-Code/HiGHS#3586 · Filter by author DoumarCharles opened on Nov 9, 2026
  

• Presolve: check column signatures first in dominated columns

  Code-qualityPresolve
  ERGO-Code/HiGHS#3585 · Filter by author DoumarCharles opened on Nov 8, 2026
  

• Mod-k separation: skip basis swaps that leave the solution unchanged

  Code-qualityMIP
  ERGO-Code/HiGHS#3584 · Filter by author DoumarCharles opened on Nov 8, 2026
  

• Presolve: avoid repeatedly collecting the same row in dominated columns

  Code-qualityMIPPresolve
  ERGO-Code/HiGHS#3583 · Filter by author DoumarCharles opened on Nov 8, 2026
  

• Duplicate column postsolve anomaly

  LPPostsolve
  ERGO-Code/HiGHS#3582 · Filter by author jajhall opened on Nov 8, 2026
  

• Presolve: avoid repeated row scans in dual fixing

  Code-qualityMIP
  ERGO-Code/HiGHS#3581 · Filter by author DoumarCharles opened on Nov 8, 2026
  3

  

• IPX: Infeasible on a feasible LP

  BugIPX
  ERGO-Code/HiGHS#3563 · Filter by author jajhall opened on Nov 6, 2026
  1

  

• Time limit ignored on a modified fiball

  BugMIP
  ERGO-Code/HiGHS#3560 · Filter by author hodangkhoinguyen opened on Nov 6, 2026
  1

• Segmentation fault on a modified pigeon-20

  BugMIP
  ERGO-Code/HiGHS#3559 · Filter by author hodangkhoinguyen opened on Nov 6, 2026
  2

  

• MIP: HighsDomain::propagate allocates a 2 x nnz buffer on every call (9-17 % of MIP time on some models)

  ERGO-Code/HiGHS#3543 · Filter by author DoumarCharles opened on Nov 4, 2026
  9

  

• HiGHS does not honour time limit with a particular model

  Code-qualityMIP
  ERGO-Code/HiGHS#3508 · Filter by author igofunke opened on Oct 30, 2026
  4

  

• LP: infeasible models end with Unknown / Solve error / Not Set on the default path; IPM says Infeasible

  BugLPSimplex
  ERGO-Code/HiGHS#3418 · Filter by author finik opened on Oct 14, 2026
  5

  

• QP ASM issues

  BugQP ASMQP
  ERGO-Code/HiGHS#3396 · Filter by author jajhall opened on Oct 11, 2026
  

• Simplex issues

  BugLPSimplex
  ERGO-Code/HiGHS#3395 · Filter by author jajhall opened on Oct 11, 2026
  4