diff --git a/clippy_lints/src/eta_reduction.rs b/clippy_lints/src/eta_reduction.rs
index a30cd87554c5..0b34bb99bc7f 100644
--- a/clippy_lints/src/eta_reduction.rs
+++ b/clippy_lints/src/eta_reduction.rs
@@ -1,7 +1,7 @@
 use rustc::lint::*;
 use rustc::ty;
 use rustc::hir::*;
-use utils::{snippet_opt, span_lint_and_then, is_adjusted};
+use utils::{snippet_opt, span_lint_and_then, is_adjusted, iter_input_pats};
 
 #[allow(missing_copy_implementations)]
 pub struct EtaPass;
@@ -49,7 +49,8 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for EtaPass {
 
 fn check_closure(cx: &LateContext, expr: &Expr) {
     if let ExprClosure(_, ref decl, eid, _) = expr.node {
-        let ex = cx.tcx.map.body(eid).value;
+        let body = cx.tcx.map.body(eid);
+        let ex = body.value;
         if let ExprCall(ref caller, ref args) = ex.node {
             if args.len() != decl.inputs.len() {
                 // Not the same number of arguments, there
@@ -71,8 +72,8 @@ fn check_closure(cx: &LateContext, expr: &Expr) {
                 },
                 _ => (),
             }
-            for (a1, a2) in decl.inputs.iter().zip(args) {
-                if let PatKind::Binding(_, _, ident, _) = a1.node {
+            for (a1, a2) in iter_input_pats(decl, body).zip(args) {
+                if let PatKind::Binding(_, _, ident, _) = a1.pat.node {
                     // XXXManishearth Should I be checking the binding mode here?
                     if let ExprPath(QPath::Resolved(None, ref p)) = a2.node {
                         if p.segments.len() != 1 {
diff --git a/clippy_lints/src/functions.rs b/clippy_lints/src/functions.rs
index 18bc644a2638..784bca403772 100644
--- a/clippy_lints/src/functions.rs
+++ b/clippy_lints/src/functions.rs
@@ -6,7 +6,7 @@ use std::collections::HashSet;
 use syntax::ast;
 use syntax::abi::Abi;
 use syntax::codemap::Span;
-use utils::{span_lint, type_is_unsafe_function};
+use utils::{span_lint, type_is_unsafe_function, iter_input_pats};
 
 /// **What it does:** Checks for functions with too many parameters.
 ///
@@ -102,7 +102,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Functions {
             }
         }
 
-        self.check_raw_ptr(cx, unsafety, decl, &body.value, nodeid);
+        self.check_raw_ptr(cx, unsafety, decl, &body, nodeid);
     }
 
     fn check_trait_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx hir::TraitItem) {
@@ -113,8 +113,8 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Functions {
             }
 
             if let hir::TraitMethod::Provided(eid) = eid {
-                let expr = cx.tcx.map.body(eid).value;
-                self.check_raw_ptr(cx, sig.unsafety, &sig.decl, &expr, item.id);
+                let body = cx.tcx.map.body(eid);
+                self.check_raw_ptr(cx, sig.unsafety, &sig.decl, &body, item.id);
             }
         }
     }
@@ -136,11 +136,14 @@ impl<'a, 'tcx> Functions {
         cx: &LateContext<'a, 'tcx>,
         unsafety: hir::Unsafety,
         decl: &'tcx hir::FnDecl,
-        expr: &'tcx hir::Expr,
+        body: &'tcx hir::Body,
         nodeid: ast::NodeId
     ) {
+        let expr = &body.value;
         if unsafety == hir::Unsafety::Normal && cx.access_levels.is_exported(nodeid) {
-            let raw_ptrs = decl.inputs.iter().filter_map(|arg| raw_ptr_arg(cx, arg)).collect::<HashSet<_>>();
+            let raw_ptrs = iter_input_pats(&decl, body).zip(decl.inputs.iter())
+                                                            .filter_map(|(arg, ty)| raw_ptr_arg(arg, ty))
+                                                            .collect::<HashSet<_>>();
 
             if !raw_ptrs.is_empty() {
                 let mut v = DerefVisitor {
@@ -154,8 +157,8 @@ impl<'a, 'tcx> Functions {
     }
 }
 
-fn raw_ptr_arg(cx: &LateContext, arg: &hir::Arg) -> Option<hir::def_id::DefId> {
-    if let (&hir::PatKind::Binding(_, def_id, _, _), &hir::TyPtr(_)) = (&arg.pat.node, &cx.tcx.map.get(arg.id)) {
+fn raw_ptr_arg(arg: &hir::Arg, ty: &hir::Ty) -> Option<hir::def_id::DefId> {
+    if let (&hir::PatKind::Binding(_, def_id, _, _), hir::TyPtr(_)) = (&arg.pat.node, ty.node) {
         Some(def_id)
     } else {
         None
diff --git a/clippy_lints/src/len_zero.rs b/clippy_lints/src/len_zero.rs
index 9cd47a8f0566..fa4a5bf67573 100644
--- a/clippy_lints/src/len_zero.rs
+++ b/clippy_lints/src/len_zero.rs
@@ -104,7 +104,7 @@ fn check_trait_items(cx: &LateContext, item: &Item, trait_items: &[TraitItemRef]
 
     if !trait_items.iter().any(|i| is_named_self(cx, i, "is_empty")) {
         if let Some(i) = trait_items.iter().find(|i| is_named_self(cx, i, "len")) {
-            if cx.access_levels.is_exported(i.id) {
+            if cx.access_levels.is_exported(i.id.node_id) {
                 span_lint(cx,
                           LEN_WITHOUT_IS_EMPTY,
                           i.span,
diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs
index b902d18d1849..cdcb271d8d75 100644
--- a/clippy_lints/src/lib.rs
+++ b/clippy_lints/src/lib.rs
@@ -8,6 +8,7 @@
 #![feature(slice_patterns)]
 #![feature(stmt_expr_attributes)]
 #![feature(repeat_str)]
+#![feature(conservative_impl_trait)]
 
 #![allow(indexing_slicing, shadow_reuse, unknown_lints, missing_docs_in_private_items)]
 #![allow(needless_lifetimes)]
diff --git a/clippy_lints/src/map_clone.rs b/clippy_lints/src/map_clone.rs
index 1418a18d3c55..311eb16514b9 100644
--- a/clippy_lints/src/map_clone.rs
+++ b/clippy_lints/src/map_clone.rs
@@ -2,7 +2,7 @@ use rustc::lint::*;
 use rustc::hir::*;
 use syntax::ast;
 use utils::{is_adjusted, match_path, match_trait_method, match_type, remove_blocks, paths, snippet,
-            span_help_and_lint, walk_ptrs_ty, walk_ptrs_ty_depth};
+            span_help_and_lint, walk_ptrs_ty, walk_ptrs_ty_depth, iter_input_pats};
 
 /// **What it does:** Checks for mapping `clone()` over an iterator.
 ///
@@ -31,18 +31,20 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
             if &*name.node.as_str() == "map" && args.len() == 2 {
                 match args[1].node {
                     ExprClosure(_, ref decl, closure_eid, _) => {
-                        let closure_expr = remove_blocks(&cx.tcx.map.body(closure_eid).value);
+                        let body = cx.tcx.map.body(closure_eid);
+                        let closure_expr = remove_blocks(&body.value);
                         if_let_chain! {[
                             // nothing special in the argument, besides reference bindings
                             // (e.g. .map(|&x| x) )
-                            let Some(arg_ident) = get_arg_name(&*decl.inputs[0]),
+                            let Some(first_arg) = iter_input_pats(decl, body).next(),
+                            let Some(arg_ident) = get_arg_name(&first_arg.pat),
                             // the method is being called on a known type (option or iterator)
                             let Some(type_name) = get_type_name(cx, expr, &args[0])
                         ], {
                             // look for derefs, for .map(|x| *x)
                             if only_derefs(cx, &*closure_expr, arg_ident) &&
                                 // .cloned() only removes one level of indirection, don't lint on more
-                                walk_ptrs_ty_depth(cx.tcx.tables().pat_ty(&*decl.inputs[0])).1 == 1
+                                walk_ptrs_ty_depth(cx.tcx.tables().pat_ty(&first_arg.pat)).1 == 1
                             {
                                 span_help_and_lint(cx, MAP_CLONE, expr.span, &format!(
                                     "you seem to be using .map() to clone the contents of an {}, consider \
diff --git a/clippy_lints/src/methods.rs b/clippy_lints/src/methods.rs
index c6986cb5456e..ab84a7f927db 100644
--- a/clippy_lints/src/methods.rs
+++ b/clippy_lints/src/methods.rs
@@ -11,7 +11,7 @@ use syntax::codemap::Span;
 use utils::{get_trait_def_id, implements_trait, in_external_macro, in_macro, is_copy, match_path, match_trait_method,
             match_type, method_chain_args, return_ty, same_tys, snippet, span_lint, span_lint_and_then,
             span_note_and_lint, walk_ptrs_ty, walk_ptrs_ty_depth, last_path_segment, single_segment_path,
-            match_def_path, is_self};
+            match_def_path, is_self, iter_input_pats};
 use utils::paths;
 use utils::sugg;
 
@@ -636,8 +636,9 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
         let parent = cx.tcx.map.get_parent(implitem.id);
         let item = cx.tcx.map.expect_item(parent);
         if_let_chain! {[
-            let hir::ImplItemKind::Method(ref sig, _) = implitem.node,
-            let Some(first_arg) = sig.decl.inputs.get(0),
+            let hir::ImplItemKind::Method(ref sig, id) = implitem.node,
+            let body = cx.tcx.map.body(id),
+            let Some(first_arg) = iter_input_pats(&sig.decl, body).next(),
             let hir::ItemImpl(_, _, _, None, _, _) = item.node,
         ], {
             // check missing trait implementations
@@ -645,7 +646,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
                 if &*name.as_str() == method_name &&
                    sig.decl.inputs.len() == n_args &&
                    out_type.matches(&sig.decl.output) &&
-                   self_kind.matches(&**first_arg, false) {
+                   self_kind.matches(&first_arg, false) {
                     span_lint(cx, SHOULD_IMPLEMENT_TRAIT, implitem.span, &format!(
                         "defining a method called `{}` on this type; consider implementing \
                          the `{}` trait or choosing a less ambiguous name", name, trait_name));
@@ -658,8 +659,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
             for &(ref conv, self_kinds) in &CONVENTIONS {
                 if_let_chain! {[
                     conv.check(&name.as_str()),
-                    let Some(explicit_self) = sig.decl.inputs.get(0),
-                    !self_kinds.iter().any(|k| k.matches(&**explicit_self, is_copy)),
+                    !self_kinds.iter().any(|k| k.matches(&first_arg, is_copy)),
                 ], {
                     let lint = if item.vis == hir::Visibility::Public {
                         WRONG_PUB_SELF_CONVENTION
@@ -668,7 +668,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
                     };
                     span_lint(cx,
                               lint,
-                              explicit_self.span,
+                              first_arg.pat.span,
                               &format!("methods called `{}` usually take {}; consider choosing a less \
                                         ambiguous name",
                                        conv,
@@ -684,7 +684,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
                !ret_ty.walk().any(|t| same_tys(cx, t, ty, implitem.id)) {
                 span_lint(cx,
                           NEW_RET_NO_SELF,
-                          first_arg.span,
+                          implitem.span,
                           "methods called `new` usually return `Self`");
             }
         }}
diff --git a/clippy_lints/src/misc.rs b/clippy_lints/src/misc.rs
index e81b9c989cd4..4af47d731726 100644
--- a/clippy_lints/src/misc.rs
+++ b/clippy_lints/src/misc.rs
@@ -9,7 +9,7 @@ use rustc_const_eval::eval_const_expr_partial;
 use rustc_const_math::ConstFloat;
 use syntax::codemap::{Span, Spanned, ExpnFormat};
 use utils::{get_item_name, get_parent_expr, implements_trait, in_macro, is_integer_literal, match_path, snippet,
-            span_lint, span_lint_and_then, walk_ptrs_ty, last_path_segment};
+            span_lint, span_lint_and_then, walk_ptrs_ty, last_path_segment, iter_input_pats};
 use utils::sugg::Sugg;
 
 /// **What it does:** Checks for function arguments and let bindings denoted as `ref`.
@@ -175,7 +175,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
         cx: &LateContext<'a, 'tcx>,
         k: FnKind<'tcx>,
         decl: &'tcx FnDecl,
-        _: &'tcx Body,
+        body: &'tcx Body,
         _: Span,
         _: NodeId
     ) {
@@ -183,11 +183,11 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
             // Does not apply to closures
             return;
         }
-        for arg in &decl.inputs {
-            if let PatKind::Binding(BindByRef(_), _, _, _) = arg.node {
+        for arg in iter_input_pats(decl, body) {
+            if let PatKind::Binding(BindByRef(_), _, _, _) = arg.pat.node {
                 span_lint(cx,
                           TOPLEVEL_REF_ARG,
-                          arg.span,
+                          arg.pat.span,
                           "`ref` directly on a function argument is ignored. Consider using a reference type instead.");
             }
         }
diff --git a/clippy_lints/src/shadow.rs b/clippy_lints/src/shadow.rs
index 17160a5a1244..6cf8a337be1a 100644
--- a/clippy_lints/src/shadow.rs
+++ b/clippy_lints/src/shadow.rs
@@ -4,7 +4,7 @@ use rustc::hir::*;
 use rustc::hir::intravisit::{Visitor, FnKind, NestedVisitorMap};
 use rustc::ty;
 use syntax::codemap::Span;
-use utils::{higher, in_external_macro, snippet, span_lint_and_then};
+use utils::{higher, in_external_macro, snippet, span_lint_and_then, iter_input_pats};
 
 /// **What it does:** Checks for bindings that shadow other bindings already in
 /// scope, while just changing reference level or mutability.
@@ -92,18 +92,18 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
         if in_external_macro(cx, body.value.span) {
             return;
         }
-        check_fn(cx, decl, &body.value);
+        check_fn(cx, decl, &body);
     }
 }
 
-fn check_fn<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, decl: &'tcx FnDecl, expr: &'tcx Expr) {
+fn check_fn<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, decl: &'tcx FnDecl, body: &'tcx Body) {
     let mut bindings = Vec::new();
-    for arg in &decl.inputs {
-        if let PatKind::Binding(_, _, ident, _) = arg.node {
+    for arg in iter_input_pats(decl, body) {
+        if let PatKind::Binding(_, _, ident, _) = arg.pat.node {
             bindings.push((ident.node, ident.span))
         }
     }
-    check_expr(cx, expr, &mut bindings);
+    check_expr(cx, &body.value, &mut bindings);
 }
 
 fn check_block<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, block: &'tcx Block, bindings: &mut Vec<(Name, Span)>) {
diff --git a/clippy_lints/src/utils/mod.rs b/clippy_lints/src/utils/mod.rs
index 5f6b1777c129..9dc623dbe5f0 100644
--- a/clippy_lints/src/utils/mod.rs
+++ b/clippy_lints/src/utils/mod.rs
@@ -906,3 +906,6 @@ pub fn is_self(slf: &Arg) -> bool {
     }
 }
 
+pub fn iter_input_pats<'tcx>(decl: &FnDecl, body: &'tcx Body) -> impl Iterator<Item=&'tcx Arg> {
+    (0..decl.inputs.len()).map(move |i| &body.arguments[i])
+}
\ No newline at end of file