1 files changed, 12 insertions, 0 deletions

diff --git a/src/test/ui/issues/issue-64593.rs b/src/test/ui/issues/issue-64593.rs
new file mode 100644
index 000000000..9e787f638
--- /dev/null
+++ b/src/test/ui/issues/issue-64593.rs
@@ -0,0 +1,12 @@
+// check-pass
+#![deny(improper_ctypes)]
+
+pub struct Error(std::num::NonZeroU32);
+
+extern "Rust" {
+    fn foo(dest: &mut [u8]) -> Result<(), Error>;
+}
+
+fn main() {
+    let _ = unsafe { foo(&mut []) };
+}