diff --git a/miri/fn_call.rs b/miri/fn_call.rs
index 15b67cca9397..51e5547de438 100644
--- a/miri/fn_call.rs
+++ b/miri/fn_call.rs
@@ -4,6 +4,7 @@ use rustc::hir::def_id::{DefId, CRATE_DEF_INDEX};
 use rustc::mir;
 use rustc_target::spec::abi::Abi;
 use rustc_data_structures::indexed_vec::Idx;
+use rustc_target::spec::abi::Abi;
 use syntax::attr;
 use syntax::codemap::Span;
 
@@ -49,7 +50,7 @@ fn write_discriminant_value<'a, 'mir, 'tcx: 'a + 'mir>(
                 if variant_index != dataful_variant {
                     let (niche_dest, niche) =
                         ecx.place_field(dest, mir::Field::new(0), layout)?;
-                    let niche_value = ((variant_index - niche_variants.start) as u128)
+                    let niche_value = ((variant_index - niche_variants.start()) as u128)
                         .wrapping_add(niche_start);
                     ecx.write_primval(niche_dest, PrimVal::Bytes(niche_value), niche.ty)?;
                 }
diff --git a/miri/helpers.rs b/miri/helpers.rs
index 3dd499f7a62e..b941e65437d9 100644
--- a/miri/helpers.rs
+++ b/miri/helpers.rs
@@ -1,7 +1,9 @@
-use super::{Pointer, EvalResult, PrimVal, EvalContext};
+use mir;
 use rustc::ty::Ty;
 use rustc::ty::layout::LayoutOf;
 
+use super::{Pointer, EvalResult, PrimVal, EvalContext};
+
 pub trait EvalContextExt<'tcx> {
     fn wrapping_pointer_offset(
         &self,
@@ -63,7 +65,7 @@ impl<'a, 'mir, 'tcx> EvalContextExt<'tcx> for EvalContext<'a, 'mir, 'tcx, super:
             }
             Ok(ptr)
         } else {
-            err!(OverflowingMath)
+            err!(Overflow(mir::BinOp::Mul))
         };
     }
 }
diff --git a/miri/lib.rs b/miri/lib.rs
index 73437d713d01..9b1888845164 100644
--- a/miri/lib.rs
+++ b/miri/lib.rs
@@ -1,7 +1,8 @@
 #![feature(
     rustc_private,
     catch_expr,
-    inclusive_range_fields
+    inclusive_range_fields,
+    inclusive_range_methods,
 )]
 
 #[macro_use]
@@ -13,6 +14,7 @@ extern crate rustc;
 extern crate rustc_mir;
 extern crate rustc_target;
 extern crate rustc_data_structures;
+extern crate rustc_target;
 extern crate syntax;
 extern crate regex;
 #[macro_use]