@@ -788,19 +788,20 @@ pub fn select_unpredictable<T>(condition: bool, true_val: T, false_val: T) -> T
788788 let mut false_val = MaybeUninit :: new ( false_val) ;
789789
790790 struct DropOnPanic < T > {
791- // Invariant: valid pointer and points to an initialized `MaybeUninit`.
792- inner : * mut MaybeUninit < T > ,
791+ // Invariant: valid pointer and points to an initialized value that is not further used,
792+ // i.e. it can be dropped by this guard.
793+ inner : * mut T ,
793794 }
794795
795796 impl < T > Drop for DropOnPanic < T > {
796797 fn drop ( & mut self ) {
797798 // SAFETY: Must be guaranteed on construction of local type `DropOnPanic`.
798- unsafe { ( * self . inner ) . assume_init_drop ( ) }
799+ unsafe { self . inner . drop_in_place ( ) }
799800 }
800801 }
801802
802- let true_ptr = ( & mut true_val) as * mut _ ;
803- let false_ptr = ( & mut false_val) as * mut _ ;
803+ let true_ptr = true_val. as_mut_ptr ( ) ;
804+ let false_ptr = false_val. as_mut_ptr ( ) ;
804805
805806 // SAFETY: The value that is not selected is dropped, and the selected one
806807 // is returned. This is necessary because the intrinsic doesn't drop the
@@ -813,10 +814,12 @@ pub fn select_unpredictable<T>(condition: bool, true_val: T, false_val: T) -> T
813814 let guard = crate :: intrinsics:: select_unpredictable ( condition, true_ptr, false_ptr) ;
814815 let drop = crate :: intrinsics:: select_unpredictable ( condition, false_ptr, true_ptr) ;
815816
816- // SAFETY: both pointers are to valid `MaybeUninit`, in both variants they do not alias but
817- // the two arguments we have selected from did alias each other.
817+ // SAFETY: both pointers are well-aligned and point to initialized values inside a
818+ // `MaybeUninit` each. In both possible values for `condition` the pointer `guard` and
819+ // `drop` do not alias (even though the two argument pairs we have selected from did alias
820+ // each other).
818821 let guard = DropOnPanic { inner : guard } ;
819- ( * drop) . assume_init_drop ( ) ;
822+ drop. drop_in_place ( ) ;
820823 crate :: mem:: forget ( guard) ;
821824
822825 // Note that it is important to use the values here. Reading from the pointer we got makes
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