Fix bug in Kokkos when shrink-wrapping with no atoms

src/KOKKOS/domain_kokkos.cpp

@@ -22,8 +22,7 @@
 
 using namespace LAMMPS_NS;
 
-#define BIG   1.0e20
-#define SMALL 1.0e-4
+static constexpr double BIG = 1.0e20;
 
 /* ---------------------------------------------------------------------- */
 
@@ -81,6 +80,11 @@ public:
 void DomainKokkos::reset_box()
 {
   // perform shrink-wrapping
+
+  // nothing to do for empty systems
+
+  if (atom->natoms == 0) return;
+
   // compute extent of atoms on this proc
   // for triclinic, this is done in lamda space