coerce reborrow multi arg test

src/test/ui/coercion/coerce-reborrow-multi-arg-fail.rs

@@ -0,0 +1,6 @@
+fn test<T>(_a: T, _b: T) {}
+
+fn main() {
+    test(&mut 7, &7);
+    //~^ mismatched types
+}

src/test/ui/coercion/coerce-reborrow-multi-arg-fail.stderr

@@ -0,0 +1,12 @@
+error[E0308]: mismatched types
+  --> $DIR/coerce-reborrow-multi-arg-fail.rs:4:18
+   |
+LL |     test(&mut 7, &7);
+   |                  ^^ types differ in mutability
+   |
+   = note: expected mutable reference `&mut {integer}`
+                      found reference `&{integer}`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.

src/test/ui/coercion/coerce-reborrow-multi-arg.rs

@@ -0,0 +1,9 @@
+// build-pass
+fn test<T>(_a: T, _b: T) {}
+
+fn main() {
+    test(&7, &7);
+    test(&7, &mut 7);
+    test::<&i32>(&mut 7, &7);
+    test::<&i32>(&mut 7, &mut 7);
+}