diff --git a/clippy_lints/src/array_indexing.rs b/clippy_lints/src/array_indexing.rs
index 4563a58f7abd..1b21cf8c5ff4 100644
--- a/clippy_lints/src/array_indexing.rs
+++ b/clippy_lints/src/array_indexing.rs
@@ -3,6 +3,7 @@ use rustc::ty;
 use rustc::hir;
 use syntax::ast::RangeLimits;
 use utils::{self, higher};
+use utils::higher::Range;
 use consts::{constant, Constant};
 
 /// **What it does:** Checks for out of bounds array indexing with a constant
@@ -73,10 +74,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for ArrayIndexing {
 
                 // Index is a constant range
                 if let Some(range) = higher::range(index) {
-                    let start = range.start.map(|start| constant(cx, start).map(|(c, _)| c));
-                    let end = range.end.map(|end| constant(cx, end).map(|(c, _)| c));
-
-                    if let Some((start, end)) = to_const_range(&start, &end, range.limits, size) {
+                    if let Some((start, end)) = to_const_range(cx, range, size) {
                         if start > size || end > size {
                             utils::span_lint(cx, OUT_OF_BOUNDS_INDEXING, e.span, "range is out of bounds");
                         }
@@ -102,20 +100,17 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for ArrayIndexing {
 
 /// Returns an option containing a tuple with the start and end (exclusive) of
 /// the range.
-fn to_const_range(
-    start: &Option<Option<Constant>>,
-    end: &Option<Option<Constant>>,
-    limits: RangeLimits,
-    array_size: u128,
-) -> Option<(u128, u128)> {
-    let start = match *start {
+fn to_const_range<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, range: Range, array_size: u128) -> Option<(u128, u128)> {
+    let s = range.start.map(|expr| constant(cx, expr).map(|(c, _)| c));
+    let start = match s {
         Some(Some(Constant::Int(x))) => x,
         Some(_) => return None,
         None => 0,
     };
 
-    let end = match *end {
-        Some(Some(Constant::Int(x))) => if limits == RangeLimits::Closed {
+    let e = range.end.map(|expr| constant(cx, expr).map(|(c, _)| c));
+    let end = match e {
+        Some(Some(Constant::Int(x))) => if range.limits == RangeLimits::Closed {
             x + 1
         } else {
             x
diff --git a/clippy_lints/src/methods.rs b/clippy_lints/src/methods.rs
index 50de299ca7d1..423be2106d16 100644
--- a/clippy_lints/src/methods.rs
+++ b/clippy_lints/src/methods.rs
@@ -680,9 +680,7 @@ impl LintPass for Pass {
 }
 
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
-    #[allow(unused_attributes)]
-    // ^ required because `cyclomatic_complexity` attribute shows up as unused
-    #[cyclomatic_complexity = "30"]
+    #[allow(cyclomatic_complexity)]
     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr) {
         if in_macro(expr.span) {
             return;
@@ -889,6 +887,7 @@ fn lint_or_fun_call(cx: &LateContext, expr: &hir::Expr, method_span: Span, name:
     }
 
     /// Check for `*or(foo())`.
+    #[allow(too_many_arguments)]
     fn check_general_case(
         cx: &LateContext,
         name: &str,
diff --git a/clippy_lints/src/utils/hir_utils.rs b/clippy_lints/src/utils/hir_utils.rs
index e790184a7aba..1f96ec2b237c 100644
--- a/clippy_lints/src/utils/hir_utils.rs
+++ b/clippy_lints/src/utils/hir_utils.rs
@@ -316,6 +316,7 @@ impl<'a, 'tcx: 'a> SpanlessHash<'a, 'tcx> {
         b.rules.hash(&mut self.s);
     }
 
+    #[allow(many_single_char_names)]
     pub fn hash_expr(&mut self, e: &Expr) {
         if let Some(e) = constant_simple(self.cx, e) {
             return e.hash(&mut self.s);
diff --git a/clippy_lints/src/utils/mod.rs b/clippy_lints/src/utils/mod.rs
index e3a7fc851b15..f71de382cade 100644
--- a/clippy_lints/src/utils/mod.rs
+++ b/clippy_lints/src/utils/mod.rs
@@ -1103,7 +1103,7 @@ pub fn without_block_comments(lines: Vec<&str>) -> Vec<&str> {
 
     let mut nest_level = 0;
 
-    for line in lines.into_iter() {
+    for line in lines {
         if line.contains("/*") {
             nest_level += 1;
             continue;
diff --git a/src/main.rs b/src/main.rs
index 5bdbaf1bc80e..aac5e97f3114 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -77,10 +77,30 @@ where
     if cfg!(windows) {
         path.set_extension("exe");
     }
+
+    let target_dir = std::env::var_os("CLIPPY_DOGFOOD")
+        .map(|_| {
+            std::env::var_os("CARGO_MANIFEST_DIR").map_or_else(
+                || {
+                    let mut fallback = std::ffi::OsString::new();
+                    fallback.push("clippy_dogfood");
+                    fallback
+                },
+                |d| {
+                    std::path::PathBuf::from(d)
+                        .join("target")
+                        .join("dogfood")
+                        .into_os_string()
+                },
+            )
+        })
+        .map(|p| ("CARGO_TARGET_DIR", p));
+
     let exit_status = std::process::Command::new("cargo")
         .args(&args)
         .env("RUSTC_WRAPPER", path)
         .env("CLIPPY_ARGS", clippy_args)
+        .envs(target_dir)
         .spawn()
         .expect("could not run cargo")
         .wait()
diff --git a/tests/dogfood.rs b/tests/dogfood.rs
index ed6451a3eb68..a2d4da9a1ca4 100644
--- a/tests/dogfood.rs
+++ b/tests/dogfood.rs
@@ -15,6 +15,7 @@ fn dogfood() {
             .arg("cargo-clippy")
             .arg("--manifest-path")
             .arg(root_dir.join("Cargo.toml"))
+            .env("CLIPPY_DOGFOOD", "true")
             .output()
             .unwrap();
         println!("status: {}", output.status);