Invoke ensure clauses before switching context from fibers; fix
@@ -1870,6 +1870,9 @@ RETRY_TRY_BLOCK:
if (mrb->c->ci == mrb->c->cibase && mrb->c->ci->pc) {
struct mrb_context *c = mrb->c;
+ while (eidx > 0) {
+ ecall(mrb, --eidx);
+ }
mrb->c = c->prev;
c->prev = NULL;
ci = mrb->c->ci;
