Replace uninitialized with MaybeUninit

alacritty_terminal/src/term/cell.rs

@@ -138,14 +138,14 @@ impl Cell {
     #[inline]
     pub fn chars(&self) -> [char; MAX_ZEROWIDTH_CHARS + 1] {
         unsafe {
-            let mut chars = [std::mem::uninitialized(); MAX_ZEROWIDTH_CHARS + 1];
-            std::ptr::write(&mut chars[0], self.c);
+            let mut chars = [std::mem::MaybeUninit::uninit(); MAX_ZEROWIDTH_CHARS + 1];
+            std::ptr::write(chars[0].as_mut_ptr(), self.c);
             std::ptr::copy_nonoverlapping(
-                self.extra.as_ptr(),
+                self.extra.as_ptr() as *mut std::mem::MaybeUninit<char>,
                 chars.as_mut_ptr().offset(1),
                 self.extra.len(),
             );
-            chars
+            std::mem::transmute(chars)
         }
     }
 

alacritty_terminal/src/term/color.rs

@@ -143,7 +143,7 @@ pub struct List([Rgb; COUNT]);
 impl<'a> From<&'a Colors> for List {
     fn from(colors: &Colors) -> List {
         // Type inference fails without this annotation
-        let mut list: List = unsafe { ::std::mem::uninitialized() };
+        let mut list = List([Rgb::default(); COUNT]);
 
         list.fill_named(colors);
         list.fill_cube(colors);

alacritty_terminal/src/tty/unix.rs

@@ -13,7 +13,6 @@
 // limitations under the License.
 //
 //! tty related functionality
-//!
 
 use crate::config::{Config, Shell};
 use crate::display::OnResize;
@@ -36,6 +35,7 @@ use std::os::unix::{
 use std::process::{Child, Command, Stdio};
 use std::ptr;
 use std::sync::atomic::{AtomicUsize, Ordering};
+use std::mem::MaybeUninit;
 
 /// Process ID of child process
 ///
@@ -91,15 +91,16 @@ struct Passwd<'a> {
 /// If `buf` is changed while `Passwd` is alive, bad thing will almost certainly happen.
 fn get_pw_entry(buf: &mut [i8; 1024]) -> Passwd<'_> {
     // Create zeroed passwd struct
-    let mut entry: libc::passwd = unsafe { ::std::mem::uninitialized() };
+    let mut entry: MaybeUninit<libc::passwd> = MaybeUninit::uninit();
 
     let mut res: *mut libc::passwd = ptr::null_mut();
 
     // Try and read the pw file.
     let uid = unsafe { libc::getuid() };
     let status = unsafe {
-        libc::getpwuid_r(uid, &mut entry, buf.as_mut_ptr() as *mut _, buf.len(), &mut res)
+        libc::getpwuid_r(uid, entry.as_mut_ptr(), buf.as_mut_ptr() as *mut _, buf.len(), &mut res)
     };
+    let entry = unsafe { entry.assume_init() };
 
     if status < 0 {
         die!("getpwuid_r failed");