From 669d159cef8584a077440779584e84d07e92894e Mon Sep 17 00:00:00 2001
From: Jim Blandy <jimb@red-bean.com>
Date: Tue, 17 Oct 2023 17:59:38 -0700
Subject: [PATCH] Let the `"strict_asserts"` feature enable `Token::root`
 assertions.

Perform run-time checks that only one root `Token` exists per thread
when the `"strict_asserts"` feature is enabled, not only in debug
builds.
---
 CHANGELOG.md         |  2 +-
 wgpu-core/src/hub.rs | 16 +++++++++-------
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e16759d4ee..75afd3d29d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -101,7 +101,6 @@ By @teoxoy in [#4185](https://github.com/gfx-rs/wgpu/pull/4185)
 - Add WinUI 3 SwapChainPanel support. By @ddrboxman in [#4191](https://github.com/gfx-rs/wgpu/pull/4191)
 
 ### Changes
-
 #### General
 
 - Omit texture store bound checks since they are no-ops if out of bounds on all APIs. By @teoxoy in [#3975](https://github.com/gfx-rs/wgpu/pull/3975)
@@ -117,6 +116,7 @@ By @teoxoy in [#4185](https://github.com/gfx-rs/wgpu/pull/4185)
 - Expose instance flags. By @nical in [4230](https://github.com/gfx-rs/wgpu/pull/4230)
 - Add support for the bgra8unorm-storage feature. By @jinleili and @nical in [#4228](https://github.com/gfx-rs/wgpu/pull/4228)
 - Calls to lost devices now return `DeviceError::Lost` instead of `DeviceError::Invalid`. By @bradwerth in [#4238]([https://github.com/gfx-rs/wgpu/pull/4238])
+- Let the `"strict_asserts"` feature enable check that wgpu-core's lock-ordering tokens are unique per thread. By @jimblandy in [#4258]([https://github.com/gfx-rs/wgpu/pull/4258])
 
 #### Vulkan
 
diff --git a/wgpu-core/src/hub.rs b/wgpu-core/src/hub.rs
index 0435a28607..6445a328ed 100644
--- a/wgpu-core/src/hub.rs
+++ b/wgpu-core/src/hub.rs
@@ -169,7 +169,9 @@ use crate::{
     storage::{Element, Storage, StorageReport},
 };
 
-#[cfg(debug_assertions)]
+use wgt::{strict_assert_eq, strict_assert_ne};
+
+#[cfg(any(debug_assertions, feature = "strict_asserts"))]
 use std::cell::Cell;
 use std::{fmt::Debug, marker::PhantomData};
 
@@ -281,7 +283,7 @@ impl<A: HalApi> Access<QuerySet<A>> for RenderPipeline<A> {}
 impl<A: HalApi> Access<QuerySet<A>> for ComputePipeline<A> {}
 impl<A: HalApi> Access<QuerySet<A>> for Sampler<A> {}
 
-#[cfg(debug_assertions)]
+#[cfg(any(debug_assertions, feature = "strict_asserts"))]
 thread_local! {
     /// Per-thread state checking `Token<Root>` creation in debug builds.
     ///
@@ -320,10 +322,10 @@ impl<'a, T> Token<'a, T> {
     ///
     /// This should only be used by `Registry` locking methods.
     pub(crate) fn new() -> Self {
-        #[cfg(debug_assertions)]
+        #[cfg(any(debug_assertions, feature = "strict_asserts"))]
         ACTIVE_TOKEN.with(|active| {
             let old = active.get();
-            assert_ne!(old, 0, "Root token was dropped");
+            strict_assert_ne!(old, 0, "Root token was dropped");
             active.set(old + 1);
         });
         Self { level: PhantomData }
@@ -336,9 +338,9 @@ impl Token<'static, Root> {
     /// Debug builds check dynamically that each thread has at most
     /// one root token at a time.
     pub fn root() -> Self {
-        #[cfg(debug_assertions)]
+        #[cfg(any(debug_assertions, feature = "strict_asserts"))]
         ACTIVE_TOKEN.with(|active| {
-            assert_eq!(0, active.replace(1), "Root token is already active");
+            strict_assert_eq!(0, active.replace(1), "Root token is already active");
         });
 
         Self { level: PhantomData }
@@ -347,7 +349,7 @@ impl Token<'static, Root> {
 
 impl<'a, T> Drop for Token<'a, T> {
     fn drop(&mut self) {
-        #[cfg(debug_assertions)]
+        #[cfg(any(debug_assertions, feature = "strict_asserts"))]
         ACTIVE_TOKEN.with(|active| {
             let old = active.get();
             active.set(old - 1);