Should restore to the root fiber for each interaction; fix
MODIFY
mrbgems/mruby-bin-mirb/tools/mirb/mirb.c
mrbgems/mruby-bin-mirb/tools/mirb/mirb.c
@@ -551,6 +551,8 @@ done:
mrb_top_self(mrb),
stack_keep);
stack_keep = proc->body.irep->nlocals;
+ /* restore to fiber */
+ mrb->c = mrb->root_c;
/* did an exception occur? */
if (mrb->exc) {
p(mrb, mrb_obj_value(mrb->exc), 0);

Should restore to the root fiber for each interaction; fix #3537