From 8de85808eccd62b505115c28483c441716b8057b Mon Sep 17 00:00:00 2001
From: Oliver Schneider <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 31 Jul 2017 15:56:50 +0200
Subject: [PATCH] Properly process ptr_op for const eval

---
 src/librustc_mir/interpret/const_eval.rs | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/librustc_mir/interpret/const_eval.rs b/src/librustc_mir/interpret/const_eval.rs
index 8a0b6d5b692..193e0f7d01a 100644
--- a/src/librustc_mir/interpret/const_eval.rs
+++ b/src/librustc_mir/interpret/const_eval.rs
@@ -179,12 +179,16 @@ fn call_intrinsic<'a>(
     fn ptr_op<'a>(
         _ecx: &EvalContext<'a, 'tcx, Self>,
         _bin_op: mir::BinOp,
-        _left: PrimVal,
+        left: PrimVal,
         _left_ty: Ty<'tcx>,
-        _right: PrimVal,
+        right: PrimVal,
         _right_ty: Ty<'tcx>,
     ) -> EvalResult<'tcx, Option<(PrimVal, bool)>> {
-        Err(ConstEvalError::NeedsRfc("Pointer arithmetic or comparison".to_string()).into())
+        if left.is_bytes() && right.is_bytes() {
+            Ok(None)
+        } else {
+            Err(ConstEvalError::NeedsRfc("Pointer arithmetic or comparison".to_string()).into())
+        }
     }
 
     fn mark_static_initialized(m: !) -> EvalResult<'tcx> {
-- 
2.44.0