show all callinfo's.

src/error.c

@@ -189,6 +189,7 @@ exc_debug_info(mrb_state *mrb, struct RObject *exc)
   mrb_callinfo *ci = mrb->ci;
   mrb_code *pc = ci->pc;
 
+  mrb_obj_iv_set(mrb, exc, mrb_intern(mrb, "ciidx"), mrb_fixnum_value(ci - mrb->cibase));
   ci--;
   while (ci >= mrb->cibase) {
     if (ci->proc && !MRB_PROC_CFUNC_P(ci->proc)) {

src/vm.c

@@ -169,9 +169,6 @@ cipush(mrb_state *mrb)
   mrb->ci->eidx = eidx;
   mrb->ci->ridx = ridx;
   mrb->ci->env = 0;
-  if (mrb->ci + 1 != mrb->ciend) {
-    mrb->ci[1].mid = 0;
-  }
   return mrb->ci;
 }
 

tools/mruby/mruby.c

@@ -166,14 +166,14 @@ static void
 showcallinfo(mrb_state *mrb)
 {
   mrb_callinfo *ci;
+  mrb_int ciidx;
   const char *filename, *sep;
   int i;
 
   printf("trace:\n");
-  for (i = 1; &mrb->cibase[i] < mrb->ciend; i++) {
+  ciidx = mrb_fixnum(mrb_obj_iv_get(mrb, mrb->exc, mrb_intern(mrb, "ciidx")));
+  for (i = 1; i <= ciidx; i++) {
     ci = &mrb->cibase[i];
-    if (ci->mid == 0)
-      break;
 
     if (MRB_PROC_CFUNC_P(ci->proc))
       filename = "(cfunc)";