Use env preserved in Proc structure in ecall(); fix
MODIFY
src/vm.c
src/vm.c
@@ -315,6 +315,7 @@ ecall(mrb_state *mrb, int i)
ci->acc = CI_ACC_SKIP;
ci->argc = 0;
ci->proc = p;
+ ci->env = p->env;
ci->nregs = p->body.irep->nregs;
ci->target_class = p->target_class;
mrb->c->stack = mrb->c->stack + ci[-1].nregs;

Use env preserved in Proc structure in ecall(); fix #3612