diff --git a/src/cache/s3.rs b/src/cache/s3.rs
index c08f8d31..30666263 100644
--- a/src/cache/s3.rs
+++ b/src/cache/s3.rs
@@ -18,7 +18,7 @@ use cache::{
     CacheWrite,
     Storage,
 };
-use futures::future::{self, Future};
+use futures::future::Future;
 use simples3::{
     AutoRefreshingProvider,
     Bucket,
@@ -90,7 +90,7 @@ impl Storage for S3Cache {
         let start = Instant::now();
         let data = match entry.finish() {
             Ok(data) => data,
-            Err(e) => return future::err(e.into()).boxed(),
+            Err(e) => return f_err(e),
         };
         let credentials = self.provider.credentials().chain_err(|| {
             "failed to get AWS credentials"
diff --git a/src/compiler/clang.rs b/src/compiler/clang.rs
index fe586386..44156e4e 100644
--- a/src/compiler/clang.rs
+++ b/src/compiler/clang.rs
@@ -109,9 +109,9 @@ fn compile<T>(creator: &T,
     let write = {
         let filename = match Path::new(&parsed_args.input).file_name() {
             Some(name) => name,
-            None => return future::err("Missing input filename".into()).boxed(),
+            None => return f_err("Missing input filename"),
         };
-
+  
         Box::new(
             write_temp_file(pool, filename.as_ref(), preprocessor_result.stdout.clone())
                  .and_then(move |(tempdir, input)| {
@@ -120,7 +120,7 @@ fn compile<T>(creator: &T,
                          Err(_) => future::err("Failed to write input file".into()),
                      }
                  })
-        )
+)
     };
 
     gcc::compile(creator, executable, preprocessor_result, parsed_args, cwd, env_vars, pool, Some(write))
diff --git a/src/compiler/gcc.rs b/src/compiler/gcc.rs
index 1cab4b25..2a400560 100644
--- a/src/compiler/gcc.rs
+++ b/src/compiler/gcc.rs
@@ -18,7 +18,7 @@ use ::compiler::{
 };
 use compiler::c::{CCompilerImpl, CCompilerKind, ParsedArguments};
 use log::LogLevel::Trace;
-use futures::future::{self, Future};
+use futures::future::Future;
 use futures_cpupool::CpuPool;
 use mock_command::{
     CommandCreatorSync,
@@ -283,7 +283,7 @@ pub fn compile<T>(creator: &T,
     let out_file = match parsed_args.outputs.get("obj") {
         Some(obj) => obj,
         None => {
-            return future::err("Missing object file output".into()).boxed()
+            return f_err("Missing object file output")
         }
     };