1 files changed, 31 insertions, 0 deletions
diff --git a/src/test/ui/transmute/transmute-different-sizes.rs b/src/test/ui/transmute/transmute-different-sizes.rs
new file mode 100644
index 000000000..690decf63
--- /dev/null
+++ b/src/test/ui/transmute/transmute-different-sizes.rs
@@ -0,0 +1,31 @@
+// normalize-stderr-test "\d+ bits" -> "N bits"
+
+// Tests that `transmute` cannot be called on types of different size.
+
+#![allow(warnings)]
+#![feature(specialization)]
+
+use std::mem::transmute;
+
+unsafe fn f() {
+    let _: i8 = transmute(16i16);
+    //~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
+}
+
+unsafe fn g<T>(x: &T) {
+    let _: i8 = transmute(x);
+    //~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
+}
+
+trait Specializable { type Output; }
+
+impl<T> Specializable for T {
+    default type Output = u16;
+}
+
+unsafe fn specializable<T>(x: u16) -> <T as Specializable>::Output {
+    transmute(x)
+    //~^ ERROR cannot transmute between types of different sizes, or dependently-sized types
+}
+
+fn main() {}