1 files changed, 25 insertions, 0 deletions
diff --git a/tests/ui/async-await/task-context-arg.rs b/tests/ui/async-await/task-context-arg.rs
new file mode 100644
index 000000000..937723ca7
--- /dev/null
+++ b/tests/ui/async-await/task-context-arg.rs
@@ -0,0 +1,25 @@
+// Checks that we don't get conflicting arguments in our debug info with a particular async function
+// structure.
+
+// edition:2021
+// compile-flags: -Cdebuginfo=2
+// build-pass
+
+#![crate_type = "lib"]
+
+use std::future::Future;
+
+// The compiler produces a closure as part of this function. That closure initially takes an
+// argument _task_context. Later, when the MIR for that closure is transformed into a generator
+// state machine, _task_context is demoted to not be an argument, but just part of an unnamed
+// argument. If we emit debug info saying that both _task_context and the unnamed argument are both
+// argument number 2, then LLVM will fail with "conflicting debug info for argument". See
+// https://github.com/rust-lang/rust/pull/109466#issuecomment-1500879195 for details.
+async fn recv_unit() {
+    std::future::ready(()).await;
+}
+
+pub fn poll_recv() {
+    // This box is necessary in order to reproduce the problem.
+    let _: Box<dyn Future<Output = ()>> = Box::new(recv_unit());
+}