From ca3d1a3211d70c1ce838e8c68eb24e3e340cac04 Mon Sep 17 00:00:00 2001
From: Folkert de Vries <folkert@folkertdev.nl>
Date: Thu, 22 Jan 2026 19:23:51 +0100
Subject: [PATCH] add c-variadic miri test

---
 src/tools/miri/tests/pass/c-variadic.rs | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 src/tools/miri/tests/pass/c-variadic.rs

diff --git a/src/tools/miri/tests/pass/c-variadic.rs b/src/tools/miri/tests/pass/c-variadic.rs
new file mode 100644
index 000000000000..a1f03db6872f
--- /dev/null
+++ b/src/tools/miri/tests/pass/c-variadic.rs
@@ -0,0 +1,18 @@
+#![feature(c_variadic)]
+
+use core::ffi::VaList;
+
+fn helper(ap: VaList) -> i32 {
+    // unsafe { ap.arg::<i32>() }
+    let _ = ap;
+    0
+}
+
+unsafe extern "C" fn variadic(a: i32, ap: ...) -> i32 {
+    assert_eq!(a, 42);
+    helper(ap)
+}
+
+fn main() {
+    assert_eq!(unsafe { variadic(42, 1) }, 1);
+}