STATUS_HEAP_CORRUPTION on startup during `RenderStartup`.

[andriyDev]

Bevy version

main (commit: ff40a6a)

Relevant system information

Windows 11.

AdapterInfo { name: "NVIDIA GeForce RTX 3080", vendor: 4318, device: 8714, device_type: DiscreteGpu, driver: "NVIDIA", driver_info: "576.88", backend: Vulkan }

What you did

Repeatedly run the clear_color example.

What went wrong

Crash during RenderStartup with STATUS_HEAP_CORRUPTION.

Additional information

So far there doesn't seem to be a reliable way to reproduce it. The best I've got is this: first, apply the following patch:

From e5027d20bd714f2c11e1db3077ce4f3e2a4debf8 Mon Sep 17 00:00:00 2001
From: andriyDev <andriydzikh@gmail.com>
Date: Fri, 1 Aug 2025 22:20:29 -0700
Subject: [PATCH] dbg

---
 crates/bevy_render/src/lib.rs  | 3 +++
 examples/window/clear_color.rs | 7 +++++++
 2 files changed, 10 insertions(+)

diff --git a/crates/bevy_render/src/lib.rs b/crates/bevy_render/src/lib.rs
index 994bc35bb..a0b69a4fd 100644
--- a/crates/bevy_render/src/lib.rs
+++ b/crates/bevy_render/src/lib.rs
@@ -586,8 +586,11 @@ unsafe fn initialize_render_app(app: &mut App) {
             // Run the `RenderStartup` if it hasn't run yet. This does mean `RenderStartup` blocks
             // the rest of the app extraction, but this is necessary since extraction itself can
             // depend on resources initialized in `RenderStartup`.
+            println!("Started RenderStartup");
             render_world.run_schedule(RenderStartup);
             should_run_startup = false;
+            println!("Finished RenderStartup");
+            std::process::exit(0);
         }
 
         {
diff --git a/examples/window/clear_color.rs b/examples/window/clear_color.rs
index 1933c4e7c..427234d1f 100644
--- a/examples/window/clear_color.rs
+++ b/examples/window/clear_color.rs
@@ -10,6 +10,7 @@ fn main() {
         .add_plugins(DefaultPlugins)
         .add_systems(Startup, setup)
         .add_systems(Update, change_clear_color)
+        .add_systems(Update, exit)
         .run();
 }
 
@@ -22,3 +23,9 @@ fn change_clear_color(input: Res<ButtonInput<KeyCode>>, mut clear_color: ResMut<
         clear_color.0 = PURPLE.into();
     }
 }
+
+fn exit(frame: Res<bevy::diagnostic::FrameCount>, mut app_exit: EventWriter<AppExit>) {
+    if frame.0 > 100 {
+        app_exit.write(AppExit::Success);
+    }
+}
-- 
2.49.0.windows.1

Next, run the following bash script (e.g., in Git Bash):

i=0; while cargo r --example clear_color ; do echo $i; i=$((i + 1)); done

Go grab a coffee... this can take a while to fail. I've gotten the heap corruption at iteration 389, though it usually happens sooner than that.

I suspect some operation we are doing isn't actually thread-safe under the hood. Making RenderStartup use the single-threaded executor seems to fix it (I got to iteration 750). I went through and listed out all the rendering operations I could find in every RenderStartup usage on main. Here is the resulting table. None of these scream "not multithread safe", especially since we do these at runtime all the time.

[atlv24]

Fixed by gfx-rs/wgpu#8043