Remove additions to conservative_is_uninhabited

Author: varkor

src/librustc/ty/sty.rs

@@ -1485,19 +1485,7 @@ impl<'a, 'gcx, 'tcx> TyS<'tcx> {
         // Uncontentious uninhabitableness check
         match self.sty {
             ty::TyNever => true,
-            // We could extend this to ADTs in which every variant is uninhabited
-            // (for enums, unions, etc.).
             ty::TyAdt(def, _) => def.variants.is_empty(),
-            ty::TyTuple(tys) => tys.iter().any(|ty| ty.conservative_is_uninhabited()),
-            ty::TyArray(ty, len) => {
-                match len.val.to_raw_bits() {
-                    // If the array is definitely non-empty, it's uninhabited if
-                    // the type of its elements is uninhabited.
-                    Some(n) if n != 0 => ty.conservative_is_uninhabited(),
-                    _ => false
-                }
-            }
-            // `ty::TyRef` is a grey area at the moment.
             _ => false
         }
     }

src/librustc_typeck/check/mod.rs

@@ -434,12 +434,14 @@ pub enum PlaceOp {
 /// wake). Tracked semi-automatically (through type variables marked
 /// as diverging), with some manual adjustments for control-flow
 /// primitives (approximating a CFG).
+///
 /// We know a node diverges in the following (conservative) situations:
 /// - A function with a parameter whose type is uninhabited necessarily diverges.
 /// - A match expression with no arms necessarily diverges.
 /// - A match expression whose arms patterns all diverge necessarily diverges.
 /// - A match expression whose arms all diverge necessarily diverges.
 /// - An expression whose type is uninhabited necessarily diverges.
+///
 /// In the above, the node will be marked as diverging `Always` or `WarnedAlways`.
 /// In any other situation, it will be marked as `Maybe`.
 #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]