test for invalid wide raw ptr

Author: RalfJung

tests/compile-fail/validity/invalid_wide_raw.rs

@@ -0,0 +1,8 @@
+fn main() {
+    trait T { }
+    #[derive(Debug)]
+    struct S {
+        x: * mut dyn T
+    }
+    dbg!(S { x: unsafe { std::mem::transmute((0usize, 0usize)) } }); //~ ERROR: encountered dangling or unaligned vtable pointer
+}