Add ICE test for bad Add::add impl item type

tests/ui/lang-items/bad-add-impl.rs

@@ -0,0 +1,18 @@
+#![feature(no_core)]
+#![feature(lang_items)]
+#![no_core]
+
+#[lang = "sized"]
+trait Sized {}
+
+#[lang = "add"]
+trait Add<T> {
+    const add: u32 = 1u32;
+}
+
+impl Add<u32> for u32 {}
+
+fn main() {
+    1u32 + 1u32;
+    //~^ ERROR cannot add `u32` to `u32`
+}

tests/ui/lang-items/bad-add-impl.stderr

@@ -0,0 +1,11 @@
+error[E0369]: cannot add `u32` to `u32`
+  --> $DIR/bad-add-impl.rs:16:10
+   |
+LL |     1u32 + 1u32;
+   |     ---- ^ ---- u32
+   |     |
+   |     u32
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0369`.