1 files changed, 17 insertions, 0 deletions
diff --git a/src/test/ui/consts/const_in_pattern/issue-78057.rs b/src/test/ui/consts/const_in_pattern/issue-78057.rs
new file mode 100644
index 000000000..69cf8404d
--- /dev/null
+++ b/src/test/ui/consts/const_in_pattern/issue-78057.rs
@@ -0,0 +1,17 @@
+#![deny(unreachable_patterns)]
+
+#[derive(PartialEq)]
+struct Opaque(i32);
+
+impl Eq for Opaque {}
+
+const FOO: Opaque = Opaque(42);
+
+fn main() {
+    match FOO {
+        FOO => {},
+        //~^ ERROR must be annotated with `#[derive(PartialEq, Eq)]`
+        _ => {}
+        //~^ ERROR unreachable pattern
+    }
+}