1 files changed, 138 insertions, 0 deletions
diff --git a/tests/ui/lint/wide_pointer_comparisons.rs b/tests/ui/lint/wide_pointer_comparisons.rs
new file mode 100644
index 000000000..8334575cf
--- /dev/null
+++ b/tests/ui/lint/wide_pointer_comparisons.rs
@@ -0,0 +1,138 @@
+// check-pass
+
+use std::rc::Rc;
+use std::sync::Arc;
+use std::cmp::PartialEq;
+
+struct A;
+struct B;
+
+trait T {}
+impl T for A {}
+impl T for B {}
+
+fn main() {
+    let ab = (A, B);
+    let a = &ab.0 as *const dyn T;
+    let b = &ab.1 as *const dyn T;
+
+    let _ = a == b;
+    //~^ WARN ambiguous wide pointer comparison
+    let _ = a != b;
+    //~^ WARN ambiguous wide pointer comparison
+    let _ = a < b;
+    //~^ WARN ambiguous wide pointer comparison
+    let _ = a <= b;
+    //~^ WARN ambiguous wide pointer comparison
+    let _ = a > b;
+    //~^ WARN ambiguous wide pointer comparison
+    let _ = a >= b;
+    //~^ WARN ambiguous wide pointer comparison
+
+    let _ = PartialEq::eq(&a, &b);
+    //~^ WARN ambiguous wide pointer comparison
+    let _ = PartialEq::ne(&a, &b);
+    //~^ WARN ambiguous wide pointer comparison
+    let _ = a.eq(&b);
+    //~^ WARN ambiguous wide pointer comparison
+    let _ = a.ne(&b);
+    //~^ WARN ambiguous wide pointer comparison
+
+    {
+        // &*const ?Sized
+        let a = &a;
+        let b = &b;
+
+        let _ = a == b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a != b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a < b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a <= b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a > b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a >= b;
+        //~^ WARN ambiguous wide pointer comparison
+
+        let _ = PartialEq::eq(a, b);
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = PartialEq::ne(a, b);
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = PartialEq::eq(&a, &b);
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = PartialEq::ne(&a, &b);
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a.eq(b);
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a.ne(b);
+        //~^ WARN ambiguous wide pointer comparison
+    }
+
+    let s = "" as *const str;
+    let _ = s == s;
+    //~^ WARN ambiguous wide pointer comparison
+
+    let s = &[8, 7][..] as *const [i32];
+    let _ = s == s;
+    //~^ WARN ambiguous wide pointer comparison
+
+    fn cmp<T: ?Sized>(a: *mut T, b: *mut T) -> bool {
+        let _ = a == b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a != b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a < b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a <= b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a > b;
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a >= b;
+        //~^ WARN ambiguous wide pointer comparison
+
+        let _ = PartialEq::eq(&a, &b);
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = PartialEq::ne(&a, &b);
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a.eq(&b);
+        //~^ WARN ambiguous wide pointer comparison
+        let _ = a.ne(&b);
+        //~^ WARN ambiguous wide pointer comparison
+
+        let a = &a;
+        let b = &b;
+        &*a == &*b
+        //~^ WARN ambiguous wide pointer comparison
+    }
+
+    {
+        macro_rules! cmp {
+            ($a:ident, $b:ident) => { $a == $b }
+            //~^ WARN ambiguous wide pointer comparison
+        }
+
+        cmp!(a, b);
+    }
+
+    {
+        // this produce weird diagnostics
+        macro_rules! cmp {
+            ($a:expr, $b:expr) => { $a == $b }
+            //~^ WARN ambiguous wide pointer comparison
+        }
+
+        cmp!(&a, &b);
+    }
+
+    let _ = std::ptr::eq(a, b);
+    let _ = std::ptr::addr_eq(a, b);
+    let _ = a as *const () == b as *const ();
+
+    let a: Rc<dyn std::fmt::Debug> = Rc::new(1);
+    Rc::ptr_eq(&a, &a);
+
+    let a: Arc<dyn std::fmt::Debug> = Arc::new(1);
+    Arc::ptr_eq(&a, &a);
+}