The first instruction was skipped mistakenly in ensure clause; fix
MODIFY
src/vm.c
src/vm.c
@@ -1329,6 +1329,7 @@ RETRY_TRY_BLOCK:
if (a > mrb->c->eidx - epos)
a = mrb->c->eidx - epos;
+ pc = pc + 1;
for (n=0; n<a; n++) {
proc = mrb->c->ensure[epos+n];
irep = proc->body.irep;
@@ -1339,7 +1340,7 @@ RETRY_TRY_BLOCK:
ci->stackent = mrb->c->stack;
ci->nregs = irep->nregs;
ci->target_class = proc->target_class;
- ci->pc = pc + 1;
+ ci->pc = pc;
ci->acc = ci[-1].nregs;
mrb->c->stack += ci->acc;
stack_extend(mrb, ci->nregs);

The first instruction was skipped mistakenly in ensure clause; fix #3811