vlistCat: set varsAllocated to nvars

src/vlist.c

@@ -372,6 +372,7 @@ void vlistCopy(int vlistID2, int vlistID1)
       int nvars = vlistptr1->nvars;
       int nlevs, varID;
 
+      //vlistptr2->varsAllocated = nvars;
       vlistptr2->vars = (var_t *) malloc(vlistptr2->varsAllocated*sizeof(var_t));
       memcpy(vlistptr2->vars, vlistptr1->vars, vlistptr2->varsAllocated*sizeof(var_t));
 
@@ -725,7 +726,11 @@ void vlistCat(int vlistID2, int vlistID1)
   nvars = nvars1 + nvars2;
   vlistptr2->nvars = nvars;
 
-  vlistptr2->vars = (var_t *) realloc(vlistptr2->vars, nvars*sizeof(var_t));
+  if ( nvars > vlistptr2->varsAllocated )
+    {
+      vlistptr2->varsAllocated = nvars;
+      vlistptr2->vars = (var_t *) realloc(vlistptr2->vars, nvars*sizeof(var_t));
+    }
   memcpy(vlistptr2->vars+nvars2, vlistptr1->vars, nvars1*sizeof(var_t));
 
   for ( varID = 0; varID < nvars1; varID++ )