From 7074346e4f092064c5a5fa276be81d08951f56c9 Mon Sep 17 00:00:00 2001
From: Niko Matsakis <niko@alum.mit.edu>
Date: Wed, 25 Feb 2015 12:21:15 -0500
Subject: Change MarkerTrait to be invariant. This is a (small) loss of
 expressiveness, but is necessary for now to work around #22806. Fixes #22655.

---
 src/libcore/marker.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

(limited to 'src/libcore')

diff --git a/src/libcore/marker.rs b/src/libcore/marker.rs
index 6c934a998de..868a671b956 100644
--- a/src/libcore/marker.rs
+++ b/src/libcore/marker.rs
@@ -275,7 +275,13 @@ macro_rules! impls{
 /// any methods, but instead is used to gate access to data.
 ///
 /// FIXME. Better documentation needed here!
-pub trait MarkerTrait : PhantomFn<Self> { }
+pub trait MarkerTrait : PhantomFn<Self,Self> { }
+//                                    ~~~~~ <-- FIXME(#22806)?
+//
+// Marker trait has been made invariant so as to avoid inf recursion,
+// but we should ideally solve the underlying problem. That's a bit
+// complicated.
+
 impl<T:?Sized> MarkerTrait for T { }
 
 /// `PhantomFn` is a marker trait for use with traits that contain
-- 
cgit 1.4.1-3-g733a5