some more clippy-based improvements

10 files changed, 20 insertions, 26 deletions

diff --git a/src/libstd/sys/common/gnu/libbacktrace.rs b/src/libstd/sys/common/gnu/libbacktrace.rs
index 7a2ca0a9f09..3b846fd462e 100644
--- a/src/libstd/sys/common/gnu/libbacktrace.rs
+++ b/src/libstd/sys/common/gnu/libbacktrace.rs
@@ -151,7 +151,7 @@ pub fn print(w: &mut Write, idx: isize, addr: *mut libc::c_void,
         };
         STATE = backtrace_create_state(filename, 0, error_cb,
                                        ptr::null_mut());
-        return STATE
+        STATE
     }
 
     ////////////////////////////////////////////////////////////////////////
diff --git a/src/libstd/sys/common/net.rs b/src/libstd/sys/common/net.rs
index 4fb3134eac9..37379596251 100644
--- a/src/libstd/sys/common/net.rs
+++ b/src/libstd/sys/common/net.rs
@@ -161,7 +161,7 @@ pub fn lookup_addr(addr: &IpAddr) -> io::Result<String> {
     };
 
     match from_utf8(data.to_bytes()) {
-        Ok(name) => Ok(name.to_string()),
+        Ok(name) => Ok(name.to_owned()),
         Err(_) => Err(io::Error::new(io::ErrorKind::Other,
                                      "failed to lookup address information"))
     }
diff --git a/src/libstd/sys/common/remutex.rs b/src/libstd/sys/common/remutex.rs
index 4df3441f87b..f3f21e47a14 100644
--- a/src/libstd/sys/common/remutex.rs
+++ b/src/libstd/sys/common/remutex.rs
@@ -67,7 +67,7 @@ impl<T> ReentrantMutex<T> {
                 data: t,
             };
             mutex.inner.init();
-            return mutex
+            mutex
         }
     }
 
@@ -145,7 +145,7 @@ impl<'mutex, T> ReentrantMutexGuard<'mutex, T> {
 impl<'mutex, T> Deref for ReentrantMutexGuard<'mutex, T> {
     type Target = T;
 
-    fn deref<'a>(&'a self) -> &'a T {
+    fn deref(&self) -> &T {
         &self.__lock.data
     }
 }
diff --git a/src/libstd/sys/common/wtf8.rs b/src/libstd/sys/common/wtf8.rs
index eb313d275a1..633e7d78a9a 100644
--- a/src/libstd/sys/common/wtf8.rs
+++ b/src/libstd/sys/common/wtf8.rs
@@ -282,19 +282,13 @@ impl Wtf8Buf {
     /// like concatenating ill-formed UTF-16 strings effectively would.
     #[inline]
     pub fn push(&mut self, code_point: CodePoint) {
-        match code_point.to_u32() {
-            trail @ 0xDC00...0xDFFF => {
-                match (&*self).final_lead_surrogate() {
-                    Some(lead) => {
-                        let len_without_lead_surrogate = self.len() - 3;
-                        self.bytes.truncate(len_without_lead_surrogate);
-                        self.push_char(decode_surrogate_pair(lead, trail as u16));
-                        return
-                    }
-                    _ => {}
-                }
+        if let trail @ 0xDC00...0xDFFF = code_point.to_u32() {
+            if let Some(lead) = (&*self).final_lead_surrogate() {
+                let len_without_lead_surrogate = self.len() - 3;
+                self.bytes.truncate(len_without_lead_surrogate);
+                self.push_char(decode_surrogate_pair(lead, trail as u16));
+                return
             }
-            _ => {}
         }
 
         // No newly paired surrogates at the boundary.
diff --git a/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs b/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs
index cdaf69c4882..8b32b5ec040 100644
--- a/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs
+++ b/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs
@@ -99,7 +99,7 @@ pub fn write(w: &mut Write) -> io::Result<()> {
         }
 
         // keep going
-        return uw::_URC_NO_REASON
+        uw::_URC_NO_REASON
     }
 }
 
diff --git a/src/libstd/sys/unix/net.rs b/src/libstd/sys/unix/net.rs
index f1a9518d08d..6d65cb838f6 100644
--- a/src/libstd/sys/unix/net.rs
+++ b/src/libstd/sys/unix/net.rs
@@ -35,7 +35,7 @@ pub fn cvt_gai(err: c_int) -> io::Result<()> {
 
     let detail = unsafe {
         str::from_utf8(CStr::from_ptr(c::gai_strerror(err)).to_bytes()).unwrap()
-            .to_string()
+            .to_owned()
     };
     Err(io::Error::new(io::ErrorKind::Other,
                        &format!("failed to lookup address information: {}",
diff --git a/src/libstd/sys/unix/os.rs b/src/libstd/sys/unix/os.rs
index 70be04b631a..af0d8da05f4 100644
--- a/src/libstd/sys/unix/os.rs
+++ b/src/libstd/sys/unix/os.rs
@@ -88,7 +88,7 @@ pub fn error_string(errno: i32) -> String {
         }
 
         let p = p as *const _;
-        str::from_utf8(CStr::from_ptr(p).to_bytes()).unwrap().to_string()
+        str::from_utf8(CStr::from_ptr(p).to_bytes()).unwrap().to_owned()
     }
 }
 
@@ -134,7 +134,7 @@ pub struct SplitPaths<'a> {
                     fn(&'a [u8]) -> PathBuf>,
 }
 
-pub fn split_paths<'a>(unparsed: &'a OsStr) -> SplitPaths<'a> {
+pub fn split_paths(unparsed: &OsStr) -> SplitPaths {
     fn bytes_to_path(b: &[u8]) -> PathBuf {
         PathBuf::from(<OsStr as OsStrExt>::from_bytes(b))
     }
@@ -142,7 +142,7 @@ pub fn split_paths<'a>(unparsed: &'a OsStr) -> SplitPaths<'a> {
     let unparsed = unparsed.as_bytes();
     SplitPaths {
         iter: unparsed.split(is_colon as fn(&u8) -> bool)
-                      .map(bytes_to_path as fn(&'a [u8]) -> PathBuf)
+                      .map(bytes_to_path as fn(&[u8]) -> PathBuf)
     }
 }
 
diff --git a/src/libstd/sys/unix/stdio.rs b/src/libstd/sys/unix/stdio.rs
index c87800a1498..ccbb14677c7 100644
--- a/src/libstd/sys/unix/stdio.rs
+++ b/src/libstd/sys/unix/stdio.rs
@@ -23,7 +23,7 @@ impl Stdin {
         let fd = FileDesc::new(libc::STDIN_FILENO);
         let ret = fd.read(data);
         fd.into_raw();
-        return ret;
+        ret
     }
 }
 
@@ -34,7 +34,7 @@ impl Stdout {
         let fd = FileDesc::new(libc::STDOUT_FILENO);
         let ret = fd.write(data);
         fd.into_raw();
-        return ret;
+        ret
     }
 }
 
@@ -45,7 +45,7 @@ impl Stderr {
         let fd = FileDesc::new(libc::STDERR_FILENO);
         let ret = fd.write(data);
         fd.into_raw();
-        return ret;
+        ret
     }
 }
 
diff --git a/src/libstd/sys/unix/thread.rs b/src/libstd/sys/unix/thread.rs
index 5a551e2b3f3..268ec7fe356 100644
--- a/src/libstd/sys/unix/thread.rs
+++ b/src/libstd/sys/unix/thread.rs
@@ -310,7 +310,7 @@ pub mod guard {
             ret = Some(stackaddr as usize + guardsize as usize);
         }
         assert_eq!(pthread_attr_destroy(&mut attr), 0);
-        return ret
+        ret
     }
 
     #[cfg(any(target_os = "linux", target_os = "android"))]
diff --git a/src/libstd/sys/unix/thread_local.rs b/src/libstd/sys/unix/thread_local.rs
index c375788fdc1..e697417675d 100644
--- a/src/libstd/sys/unix/thread_local.rs
+++ b/src/libstd/sys/unix/thread_local.rs
@@ -18,7 +18,7 @@ pub type Key = pthread_key_t;
 pub unsafe fn create(dtor: Option<unsafe extern fn(*mut u8)>) -> Key {
     let mut key = 0;
     assert_eq!(pthread_key_create(&mut key, dtor), 0);
-    return key;
+    key
 }
 
 #[inline]