1 files changed, 23 insertions, 0 deletions
diff --git a/src/test/ui/unsafe/unsafe-fn-autoderef.rs b/src/test/ui/unsafe/unsafe-fn-autoderef.rs
new file mode 100644
index 000000000..60460fc6e
--- /dev/null
+++ b/src/test/ui/unsafe/unsafe-fn-autoderef.rs
@@ -0,0 +1,23 @@
+struct Rec {
+    f: isize
+}
+
+fn f(p: *const Rec) -> isize {
+
+    // Test that * ptrs do not autoderef.  There is a deeper reason for
+    // prohibiting this, beyond making unsafe things annoying (which doesn't
+    // actually seem desirable to me).  The deeper reason is that if you
+    // have a type like:
+    //
+    //    enum foo = *foo;
+    //
+    // you end up with an infinite auto-deref chain, which is
+    // currently impossible (in all other cases, infinite auto-derefs
+    // are prohibited by various checks, such as that the enum is
+    // instantiable and so forth).
+
+    return p.f; //~ ERROR no field `f` on type `*const Rec`
+}
+
+fn main() {
+}