Fix assertion in MaybeUninit::array_assume_init() for zero-length arrays

Author: hyd-dev

library/core/src/mem/maybe_uninit.rs

@@ -839,7 +839,7 @@ impl<T> MaybeUninit<T> {
         // * MaybeUnint does not drop, so there are no double-frees
         // And thus the conversion is safe
         unsafe {
-            intrinsics::assert_inhabited::<T>();
+            intrinsics::assert_inhabited::<[T; N]>();
             (&array as *const _ as *const [T; N]).read()
         }
     }

library/core/tests/mem.rs

@@ -152,6 +152,8 @@ fn uninit_array_assume_init() {
     let array = unsafe { MaybeUninit::array_assume_init(array) };
 
     assert_eq!(array, [3, 1, 4, 1, 5]);
+
+    let [] = unsafe { MaybeUninit::<!>::array_assume_init([]) };
 }
 
 #[test]