REnv uses obj->c as env link; no super

include/mruby/class.h

@@ -41,6 +41,8 @@ mrb_class(mrb_state *mrb, mrb_value v)
     return mrb->float_class;
   case MRB_TT_CPTR:
     return mrb->object_class;
+  case MRB_TT_ENV:
+    return NULL;
   default:
     return mrb_obj_ptr(v)->c;
   }

src/proc.c

@@ -70,6 +70,7 @@ mrb_proc_new_cfunc(mrb_state *mrb, mrb_func_t func)
   p = (struct RProc*)mrb_obj_alloc(mrb, MRB_TT_PROC, mrb->proc_class);
   p->body.func = func;
   p->flags |= MRB_PROC_CFUNC;
+  p->env = 0;
 
   return p;
 }