1 files changed, 1 insertions, 0 deletions
diff --git a/imemo.c b/imemo.c
index ce27ea5601..fc557a3144 100644
--- a/imemo.c
+++ b/imemo.c
@@ -89,6 +89,7 @@ rb_alloc_tmp_buffer_with_count(volatile VALUE *store, size_t size, size_t cnt)
 void
 rb_free_tmp_buffer(volatile VALUE *store)
 {
+    if (!*store) return;
     rb_imemo_tmpbuf_t *s = (rb_imemo_tmpbuf_t*)ATOMIC_VALUE_EXCHANGE(*store, 0);
     if (s) {
         void *ptr = ATOMIC_PTR_EXCHANGE(s->ptr, 0);