From db36c8bcc31ec4ec4dd12b7efef0962199d0e56a Mon Sep 17 00:00:00 2001
From: Axel Kohlmeyer <akohlmey@gmail.com>
Date: Fri, 21 Oct 2016 14:51:09 -0400
Subject: [PATCH] stop with error, if molecule command requires special bond
 auto-generation before box is defined

---
 src/molecule.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/molecule.cpp b/src/molecule.cpp
index 5e9aa292d0..0febb784c8 100644
--- a/src/molecule.cpp
+++ b/src/molecule.cpp
@@ -595,6 +595,10 @@ void Molecule::read(int flag)
   // set maxspecial on first pass, so allocate() has a size
 
   if (bondflag && specialflag == 0) {
+    if (domain->box_exist == 0)
+      error->all(FLERR,"Cannot auto-generate special bonds before "
+                       "simulation box is defined");
+
     maxspecial = atom->maxspecial;
     if (flag) {
       special_generate();