Need to clear `mrb->c->cibase->ridx` (toplevel ridx) at L_STOP; fix #4092

This problem only appears when `mrb` executed multiple times (i.e. `mirb`)

1 files changed, 1 insertions, 0 deletions

diff --git a/src/vm.c b/src/vm.c
index c8088d22e..98e554607 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -2954,6 +2954,7 @@ RETRY_TRY_BLOCK:
       while (mrb->c->eidx > 0) {
         ecall(mrb);
       }
+      mrb->c->cibase->ridx = 0;
       ERR_PC_CLR(mrb);
       mrb->jmp = prev_jmp;
       if (mrb->exc) {