make cioff in struct REnv from int to ptrdiff_t; close #2149

include/mruby/proc.h

@@ -17,7 +17,7 @@ struct REnv {
   MRB_OBJECT_HEADER;
   mrb_value *stack;
   mrb_sym mid;
-  int cioff;
+  ptrdiff_t cioff;
 };
 
 #define MRB_ENV_STACK_LEN(e) ((e)->flags)

src/proc.c

@@ -43,7 +43,7 @@ closure_setup(mrb_state *mrb, struct RProc *p, int nlocals)
     e = (struct REnv*)mrb_obj_alloc(mrb, MRB_TT_ENV, (struct RClass*)mrb->c->ci->proc->env);
     MRB_ENV_STACK_LEN(e)= (unsigned int)nlocals;
     e->mid = mrb->c->ci->mid;
-    e->cioff = mrb->c->ci - mrb->c->cibase;
+     e->cioff = mrb->c->ci - mrb->c->cibase;
     e->stack = mrb->c->stack;
     mrb->c->ci->env = e;
   }