Add search_started flag

Author: Opt-Mucca

highs/mip/HighsDomain.cpp

@@ -2059,6 +2059,8 @@ void HighsDomain::changeBound(HighsDomainChange boundchg, Reason reason) {
   if (binary && !infeasible_ && isFixed(boundchg.column))
     // tried to only modify cliquetable before the dive
     // but when I try the condition below breaks lseu and I don't know why yet
+    // MT: This code should be alright. It only uses the clique table.
+    // (It doesn't modify anything but the domain?)
     // if (mipsolver->mipdata_->workers.size() <= 1)
     mipsolver->mipdata_->cliquetable.addImplications(
         *this, boundchg.column, col_lower_[boundchg.column] > 0.5);

highs/mip/HighsMipSolver.cpp

@@ -142,6 +142,7 @@ void HighsMipSolver::run() {
   HighsMipWorker& master_worker = mipdata_->workers.at(0);
 
 restart:
+  search_started = false;
   if (modelstatus_ == HighsModelStatus::kNotset) {
     // Check limits have not been reached before evaluating root node
     if (mipdata_->checkLimits()) {
@@ -308,10 +309,12 @@ void HighsMipSolver::run() {
   // Initialize worker relaxations and mipworkers
   // todo lps and workers are still empty right now
 
+  search_started = true;
   const HighsInt mip_search_concurrency = options_mip_->mip_search_concurrency;
   const HighsInt num_worker = mip_search_concurrency - 1;
+
   for (int i = 0; i < num_worker; i++) {
-    mipdata_->lps.push_back(HighsLpRelaxation(*this));
+    mipdata_->lps.emplace_back(*this);
     mipdata_->workers.emplace_back(*this, mipdata_->lps.back());
   }
 

highs/mip/HighsMipSolver.h

@@ -56,6 +56,9 @@ class HighsMipSolver {
 
   HighsMipAnalysis analysis_;
 
+  // concurrency related information
+  bool search_started;
+
   void run();
 
   HighsInt numCol() const { return model_->num_col_; }