From b53a0f2c9e96778a044cb72472aa898f9804471d Mon Sep 17 00:00:00 2001
From: Matthew Maurer <mmaurer@google.com>
Date: Thu, 4 Apr 2024 22:06:58 +0000
Subject: [PATCH] CFI: Add test for `call_once` addr taken

One of the proposed ways to reduce the non-passed argument erasure would
cause this test to fail. Adding this now ensures that any attempt to
reduce non-passed argument erasure won't make the same mistake.
---
 tests/ui/sanitizer/cfi-closures.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tests/ui/sanitizer/cfi-closures.rs b/tests/ui/sanitizer/cfi-closures.rs
index f3d9be35716..9f9002da674 100644
--- a/tests/ui/sanitizer/cfi-closures.rs
+++ b/tests/ui/sanitizer/cfi-closures.rs
@@ -77,3 +77,14 @@ fn closure_addr_taken() {
     let call = Fn::<()>::call;
     use_closure(call, &f);
 }
+
+fn use_closure_once<C>(call: extern "rust-call" fn(C, ()) -> i32, f: C) -> i32 {
+    call(f, ())
+}
+
+#[test]
+fn closure_once_addr_taken() {
+    let g = || 3;
+    let call2 = FnOnce::<()>::call_once;
+    use_closure_once(call2, g);
+}