From 7e54296c6d346803efb51da9850783547c33f1df Mon Sep 17 00:00:00 2001
From: Matt Page <mpage@meta.com>
Date: Thu, 18 Jan 2024 16:51:16 -0800
Subject: [PATCH] Assert valid occupancy when adding to ringbuf

---
 Modules/_queuemodule.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Modules/_queuemodule.c b/Modules/_queuemodule.c
index a6e9c43cbfac53..5f4a141a9ac93b 100644
--- a/Modules/_queuemodule.c
+++ b/Modules/_queuemodule.c
@@ -154,6 +154,8 @@ RingBuf_Get(RingBuf *buf)
 static int
 RingBuf_Put(RingBuf *buf, PyObject *item)
 {
+    assert(buf->num_items <= buf->items_cap);
+
     if (buf->num_items == buf->items_cap) {
         // Buffer is full, grow it.
         if (resize_ringbuf(buf, buf->items_cap * 2) < 0) {