From f8037ffda4d96bf7b61f4597416209768b9c2d74 Mon Sep 17 00:00:00 2001
From: Lev Nachmanson <levnach@hotmail.com>
Date: Mon, 27 Apr 2020 15:29:09 -0700
Subject: [PATCH] always call find_feasible_solution in
 move_nbasic_columns_to_bounds()

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
---
 src/math/lp/int_cube.cpp   | 2 +-
 src/math/lp/lar_solver.cpp | 8 +-------
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/src/math/lp/int_cube.cpp b/src/math/lp/int_cube.cpp
index fbd5065c2..49398bb7a 100644
--- a/src/math/lp/int_cube.cpp
+++ b/src/math/lp/int_cube.cpp
@@ -35,6 +35,7 @@ namespace lp {
         lra.push();
         if (!tighten_terms_for_cube()) {
             lra.pop();
+            lra.set_status(lp_status::OPTIMAL);
             return lia_move::undef;
         }
         
@@ -42,7 +43,6 @@ namespace lp {
         if (st != lp_status::FEASIBLE && st != lp_status::OPTIMAL) {
             TRACE("cube", tout << "cannot find a feasiblie solution";);
             lra.pop();
-            lra.set_status(lp_status::OPTIMAL);
             lra.move_non_basic_columns_to_bounds();
             // it can happen that we found an integer solution here
             return !lra.r_basis_has_inf_int()? lia_move::sat: lia_move::undef;
diff --git a/src/math/lp/lar_solver.cpp b/src/math/lp/lar_solver.cpp
index 2f870d39d..bdaf32e88 100644
--- a/src/math/lp/lar_solver.cpp
+++ b/src/math/lp/lar_solver.cpp
@@ -465,14 +465,9 @@ void lar_solver::prepare_costs_for_r_solver(const lar_term & term) {
     lp_assert(rslv.reduced_costs_are_correct_tableau());
 }
 
-bool feasible(lp_status st) {
-    return st == lp_status::FEASIBLE || st == lp_status::OPTIMAL;
-}
-
 void lar_solver::move_non_basic_columns_to_bounds() {
     auto & lcs = m_mpq_lar_core_solver;
     bool change = false;
-    bool feas = feasible(get_status());
     for (unsigned j : lcs.m_r_nbasis) {
         if (move_non_basic_column_to_bounds(j))
             change = true;
@@ -481,9 +476,8 @@ void lar_solver::move_non_basic_columns_to_bounds() {
     if (settings().simplex_strategy() == simplex_strategy_enum::tableau_costs && change)
         update_x_and_inf_costs_for_columns_with_changed_bounds_tableau();
     
-    if (feas && change) {
+    if (change) {
         find_feasible_solution();
-        SASSERT(feasible(get_status()));
     }
 }