--- spack-src/gmodel.cpp.org	2019-12-13 10:43:51.578849661 +0900
+++ spack-src/gmodel.cpp	2019-12-13 10:54:55.467737618 +0900
@@ -30,9 +30,9 @@
     /* PLANE   = */ "Physical Surface",
     /* RULED   = */ "Physical Surface",
     /* VOLUME  = */ "Physical Volume",
-    /* LOOP    = */ 0,
-    /* SHELL   = */ 0,
-    /* GROUP   = */ 0};
+    /* LOOP    = */ nullptr,
+    /* SHELL   = */ nullptr,
+    /* GROUP   = */ nullptr};
 
 int const type_dims[NTYPES] = {
     /* POINT   = */ 0,
@@ -63,11 +63,6 @@
   return v.at(std::size_t(i));
 }
 
-template <typename T>
-static int size(std::vector<T> const& v) {
-  return int(v.size());
-}
-
 int is_entity(int t) { return t <= VOLUME; }
 
 int is_face(int t) { return t == PLANE || t == RULED; }
@@ -452,7 +447,7 @@
   auto loop = new_loop();
   add_use(loop, FORWARD, start);
   add_use(loop, FORWARD, right.middle);
-  ObjPtr end = 0;
+  ObjPtr end = nullptr;
   switch (start->type) {
     case LINE: {
       end = new_line2(std::dynamic_pointer_cast<Point>(left.end),
@@ -492,7 +487,7 @@
       break;
     }
     default:
-      end = 0;
+      end = nullptr;
       break;
   }
   add_use(loop, REVERSE, end);
@@ -508,7 +503,7 @@
       middle = new_ruled2(loop);
       break;
     default:
-      middle = 0;
+      middle = nullptr;
       break;
   }
   return Extruded{middle, end};