From 08c0460e32aa678f3b5bc0abf35b543d07dc246e Mon Sep 17 00:00:00 2001
From: Connor Fitzgerald <connorwadefitzgerald@gmail.com>
Date: Thu, 4 Jun 2020 23:42:59 -0400
Subject: [PATCH] Add assert that old SwapChainOutput is dead after SwapChain
 is remade

---
 wgpu-core/src/device/mod.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/wgpu-core/src/device/mod.rs b/wgpu-core/src/device/mod.rs
index 2392ec7b8b..10024a15ad 100644
--- a/wgpu-core/src/device/mod.rs
+++ b/wgpu-core/src/device/mod.rs
@@ -2288,6 +2288,10 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
 
         let sc_id = surface_id.to_swap_chain_id(B::VARIANT);
         if let Some(sc) = swap_chain_guard.remove(sc_id) {
+            assert!(
+                sc.acquired_view_id.is_none(),
+                "SwapChainOutput must be dropped before a new SwapChain is made."
+            );
             unsafe {
                 device.raw.destroy_semaphore(sc.semaphore);
             }