1 files changed, 18 insertions, 0 deletions
diff --git a/tests/ui/consts/const-eval/ub-enum-overwrite.rs b/tests/ui/consts/const-eval/ub-enum-overwrite.rs
new file mode 100644
index 00000000000..086a1001d11
--- /dev/null
+++ b/tests/ui/consts/const-eval/ub-enum-overwrite.rs
@@ -0,0 +1,18 @@
+#![feature(const_mut_refs)]
+
+enum E {
+    A(u8),
+    B,
+}
+
+const _: u8 = {
+    let mut e = E::A(1);
+    let p = if let E::A(x) = &mut e { x as *mut u8 } else { unreachable!() };
+    // Make sure overwriting `e` uninitializes other bytes
+    e = E::B;
+    unsafe { *p }
+    //~^ ERROR evaluation of constant value failed
+    //~| uninitialized
+};
+
+fn main() {}