fix some uses I missed

Author: RalfJung

src/libstd/sys/sgx/ext/arch.rs

@@ -28,7 +28,7 @@ const ENCLU_EGETKEY: u32 = 1;
 #[unstable(feature = "sgx_platform", issue = "56975")]
 pub fn egetkey(request: &Align512<[u8; 512]>) -> Result<Align16<[u8; 16]>, u32> {
     unsafe {
-        let mut out = MaybeUninit::uninitialized();
+        let mut out = MaybeUninit::uninit();
         let error;
 
         asm!(
@@ -41,7 +41,7 @@ pub fn egetkey(request: &Align512<[u8; 512]>) -> Result<Align16<[u8; 16]>, u32>
         );
 
         match error {
-            0 => Ok(out.into_initialized()),
+            0 => Ok(out.assume_init()),
             err => Err(err),
         }
     }
@@ -58,7 +58,7 @@ pub fn ereport(
     reportdata: &Align128<[u8; 64]>,
 ) -> Align512<[u8; 432]> {
     unsafe {
-        let mut report = MaybeUninit::uninitialized();
+        let mut report = MaybeUninit::uninit();
 
         asm!(
             "enclu"
@@ -69,6 +69,6 @@ pub fn ereport(
               "{rdx}"(report.as_mut_ptr())
         );
 
-        report.into_initialized()
+        report.assume_init()
     }
 }

src/libstd/sys/sgx/rwlock.rs

@@ -252,9 +252,9 @@ mod tests {
         ];
 
         let mut init = MaybeUninit::<RWLock>::zeroed();
-        init.set(RWLock::new());
+        init.write(RWLock::new());
         assert_eq!(
-            mem::transmute::<_, [u8; 128]>(init.into_inner()).as_slice(),
+            mem::transmute::<_, [u8; 128]>(init.assume_init()).as_slice(),
             RWLOCK_INIT
         );
     }

src/libstd/sys/windows/mutex.rs

@@ -154,7 +154,7 @@ unsafe impl Sync for ReentrantMutex {}
 
 impl ReentrantMutex {
     pub fn uninitialized() -> ReentrantMutex {
-        ReentrantMutex { inner: UnsafeCell::new(MaybeUninit::uninitialized()) }
+        ReentrantMutex { inner: UnsafeCell::new(MaybeUninit::uninit()) }
     }
 
     pub unsafe fn init(&mut self) {

src/test/codegen/box-maybe-uninit.rs

@@ -12,5 +12,8 @@ pub fn box_uninitialized() -> Box<MaybeUninit<usize>> {
     // CHECK-NOT: alloca
     // CHECK-NOT: memcpy
     // CHECK-NOT: memset
-    Box::new(MaybeUninit::uninitialized())
+    Box::new(MaybeUninit::uninit())
 }
+
+// FIXME: add a test for a bigger box. Currently broken, see
+// https://github.com/rust-lang/rust/issues/58201.

src/test/run-pass/panic-uninitialized-zeroed.rs

@@ -36,7 +36,7 @@ fn main() {
 
         assert_eq!(
             panic::catch_unwind(|| {
-                mem::MaybeUninit::<!>::uninitialized().into_initialized()
+                mem::MaybeUninit::<!>::uninit().assume_init()
             }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
                 s == "Attempted to instantiate uninhabited type !"
             })),
@@ -63,7 +63,7 @@ fn main() {
 
         assert_eq!(
             panic::catch_unwind(|| {
-                mem::MaybeUninit::<Foo>::uninitialized().into_initialized()
+                mem::MaybeUninit::<Foo>::uninit().assume_init()
             }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
                 s == "Attempted to instantiate uninhabited type Foo"
             })),
@@ -90,7 +90,7 @@ fn main() {
 
         assert_eq!(
             panic::catch_unwind(|| {
-                mem::MaybeUninit::<Bar>::uninitialized().into_initialized()
+                mem::MaybeUninit::<Bar>::uninit().assume_init()
             }).err().and_then(|a| a.downcast_ref::<String>().map(|s| {
                 s == "Attempted to instantiate uninhabited type Bar"
             })),