Deal with potential error returned by FHsolver::solve

Author: filikat

highs/ipm/hipo/factorhighs/Numeric.cpp

@@ -17,7 +17,7 @@ Int Numeric::solve(std::vector<double>& x, Int* solve_count,
                    double* omega) const {
   // Return the number of solves performed
 
-  assert(sn_columns_);
+  if (!sn_columns_ || !S_) return kRetInvalidPointer;
 
   // initialise solve handler
   SH_.reset(new HybridSolveHandler(*S_, *sn_columns_, swaps_, pivot_2x2_));

highs/ipm/hipo/factorhighs/ReturnValues.h

@@ -10,6 +10,7 @@ enum RetValue {
   kRetInvalidPivot,
   kRetMetisError,
   kRetIntOverflow,
+  kRetInvalidPointer,
   kRetGeneric
 };
 

highs/ipm/hipo/ipm/FactorHiGHSSolver.cpp

@@ -353,7 +353,7 @@ Int FactorHiGHSSolver::solveNE(const std::vector<double>& rhs,
   Clock clock;
   Int solve_count;
   double final_res;
-  Int solve_status = FH_.solve(lhs, &solve_count, &final_res);
+  if (FH_.solve(lhs, &solve_count, &final_res)) return kStatusErrorSolve;
   if (info_) {
     info_->solve_time += clock.stop();
     info_->solve_number += solve_count;
@@ -383,7 +383,7 @@ Int FactorHiGHSSolver::solveAS(const std::vector<double>& rhs_x,
   Clock clock;
   Int solve_count;
   double final_res;
-  Int solve_status = FH_.solve(rhs, &solve_count, &final_res);
+  if (FH_.solve(rhs, &solve_count, &final_res)) return kStatusErrorSolve;
   if (info_) {
     info_->solve_time += clock.stop();
     info_->solve_number += solve_count;