stdio and c_vec cleanup

src/c_str.rs

@@ -117,7 +117,7 @@ impl<'a, T: Kind> NulStr<'a, T> {
     /// The ptr must be valid up to and including the first NUL byte from the base ptr.
     pub const unsafe fn from_ptr(ptr: *const T::C) -> Self {
         Self {
-            ptr: unsafe { NonNull::new_unchecked(ptr as *mut T::C) },
+            ptr: unsafe { NonNull::new_unchecked(ptr.cast_mut()) },
             _marker: PhantomData,
         }
     }

src/c_vec.rs

@@ -37,7 +37,7 @@ impl<T> CVec<T> {
         }
     }
     fn check_bounds(i: usize) -> Result<usize, AllocError> {
-        if i > core::isize::MAX as usize {
+        if i > isize::MAX as usize {
             Err(AllocError)
         } else {
             Ok(i)
@@ -53,7 +53,7 @@ impl<T> CVec<T> {
             return Ok(Self::new());
         }
         let size = Self::check_mul(cap, mem::size_of::<T>())?;
-        let ptr = NonNull::new(unsafe { platform::alloc(size) as *mut T }).ok_or(AllocError)?;
+        let ptr = NonNull::new(unsafe { platform::alloc(size).cast::<T>() }).ok_or(AllocError)?;
         Ok(Self { ptr, len: 0, cap })
     }
     unsafe fn resize(&mut self, cap: usize) -> Result<(), AllocError> {
@@ -62,11 +62,11 @@ impl<T> CVec<T> {
             NonNull::dangling()
         } else if self.cap > 0 {
             NonNull::new(
-                unsafe { platform::realloc(self.ptr.as_ptr() as *mut c_void, size) } as *mut T,
+                unsafe { platform::realloc(self.ptr.as_ptr().cast::<c_void>(), size) }.cast::<T>(),
             )
             .ok_or(AllocError)?
         } else {
-            NonNull::new((unsafe { platform::alloc(size) }) as *mut T).ok_or(AllocError)?
+            NonNull::new((unsafe { platform::alloc(size) }).cast::<T>()).ok_or(AllocError)?
         };
         self.ptr = ptr;
         self.cap = cap;
@@ -90,7 +90,7 @@ impl<T> CVec<T> {
             .ok_or(AllocError)
             .and_then(Self::check_bounds)?;
         if required_len > self.cap {
-            let new_cap = cmp::min(required_len.next_power_of_two(), core::isize::MAX as usize);
+            let new_cap = cmp::min(required_len.next_power_of_two(), isize::MAX as usize);
             unsafe {
                 self.resize(new_cap)?;
             }

src/header/stdio/mod.rs

@@ -1124,7 +1124,7 @@ pub unsafe extern "C" fn puts(s: *const c_char) -> c_int {
     if stream.write_all(&buf).is_err() {
         return -1;
     }
-    if stream.write(&[b'\n']).is_err() {
+    if stream.write(b"\n").is_err() {
         return -1;
     }
     0

src/header/stdio/printf.rs

@@ -412,7 +412,7 @@ fn fmt_float_exp<W: Write>(
 
     pad(w, !left, b' ', len..pad_space)?;
     let bytes = if string.starts_with('-') {
-        w.write_all(&[b'-'])?;
+        w.write_all(b"-")?;
         &string.as_bytes()[1..]
     } else {
         string.as_bytes()
@@ -438,7 +438,7 @@ fn fmt_float_normal<W: Write>(
 
     pad(w, !left, b' ', string.len()..pad_space)?;
     let bytes = if string.starts_with('-') {
-        w.write_all(&[b'-'])?;
+        w.write_all(b"-")?;
         &string.as_bytes()[1..]
     } else {
         string.as_bytes()
@@ -477,7 +477,7 @@ fn fmt_float_nonfinite<W: Write>(
     // Infinity is always padded with spaces, rather than zeroes
     pad(w, !left, b' ', string.len()..pad_space + pad_zero)?;
     if float.is_sign_negative() {
-        w.write_all(&[b'-'])?;
+        w.write_all(b"-")?;
     }
     w.write_all(string.as_bytes())?;
     pad(w, left, b' ', string.len()..pad_space + pad_zero)?;
@@ -748,7 +748,7 @@ pub(crate) unsafe fn inner_printf<T: c_str::Kind>(
         });
 
         match fmtkind {
-            FmtKind::Percent => w.write_all(&[b'%'])?,
+            FmtKind::Percent => w.write_all(b"%")?,
             FmtKind::Signed => {
                 let string = match unsafe {
                     varargs.get(index, &mut ap, Some((arg.fmtkind, arg.intkind)))
@@ -782,13 +782,13 @@ pub(crate) unsafe fn inner_printf<T: c_str::Kind>(
 
                 let bytes = if positive {
                     if sign_reserve {
-                        w.write_all(&[b' '])?;
+                        w.write_all(b" ")?;
                     } else if sign_always {
-                        w.write_all(&[b'+'])?;
+                        w.write_all(b"+")?;
                     }
                     string.as_bytes()
                 } else {
-                    w.write_all(&[b'-'])?;
+                    w.write_all(b"-")?;
                     &string.as_bytes()[1..]
                 };
                 pad(w, true, b'0', len..precision.unwrap_or(pad_zero))?;

src/header/sys_mman/mod.rs

@@ -154,10 +154,10 @@ pub unsafe extern "C" fn munmap(addr: *mut c_void, len: size_t) -> c_int {
 }
 
 #[cfg(target_os = "linux")]
-static SHM_PATH: &'static [u8] = b"/dev/shm/";
+static SHM_PATH: &[u8] = b"/dev/shm/";
 
 #[cfg(target_os = "redox")]
-static SHM_PATH: &'static [u8] = b"/scheme/shm/";
+static SHM_PATH: &[u8] = b"/scheme/shm/";
 
 unsafe fn shm_path(name: *const c_char) -> CString {
     let name_c = unsafe { CStr::from_ptr(name) };