diff -up a/src/CoinPresolveMatrix.hpp b/src/CoinPresolveMatrix.hpp
--- a/src/CoinPresolveMatrix.hpp	2019-01-06 12:38:09.000000000 -0700
+++ b/src/CoinPresolveMatrix.hpp	2019-06-18 15:25:46.945705988 -0600
@@ -346,6 +346,7 @@ public:
   /// Set row status (<i>i.e.</i>, status of artificial for this row)
   inline void setRowStatus(int sequence, Status status)
   {
+    if (rowstat_ == nullptr) return;
     unsigned char &st_byte = rowstat_[sequence];
     st_byte = static_cast< unsigned char >(st_byte & (~7));
     st_byte = static_cast< unsigned char >(st_byte | status);
@@ -363,6 +364,7 @@ public:
   /// Set column status (<i>i.e.</i>, status of primal variable)
   inline void setColumnStatus(int sequence, Status status)
   {
+    if (colstat_ == nullptr) return;
     unsigned char &st_byte = colstat_[sequence];
     st_byte = static_cast< unsigned char >(st_byte & (~7));
     st_byte = static_cast< unsigned char >(st_byte | status);