1 files changed, 27 insertions, 0 deletions
diff --git a/tests/ui/transmute/issue-115402-overflow-size.rs b/tests/ui/transmute/issue-115402-overflow-size.rs
new file mode 100644
index 000000000..91168041e
--- /dev/null
+++ b/tests/ui/transmute/issue-115402-overflow-size.rs
@@ -0,0 +1,27 @@
+#![crate_type = "lib"]
+#![feature(transmutability)]
+mod assert {
+    use std::mem::BikeshedIntrinsicFrom;
+    struct Context;
+
+    pub fn is_maybe_transmutable<Src, Dst>()
+    where
+        Dst: BikeshedIntrinsicFrom<Src, Context>,
+    {
+    }
+}
+
+fn main() {
+    pub union Uninit {
+        a: [u8; usize::MAX],
+    }
+
+    #[repr(C)]
+    struct ExplicitlyPadded(Uninit);
+
+    assert::is_maybe_transmutable::<(), ExplicitlyPadded>();
+    //~^ ERROR `()` cannot be safely transmuted into `ExplicitlyPadded`
+
+    assert::is_maybe_transmutable::<ExplicitlyPadded, ()>();
+    //~^ ERROR `ExplicitlyPadded` cannot be safely transmuted into `()`
+}