Restrict access to the private field of newtype indexes

Author: oli-obk

compiler/rustc_macros/src/newtype.rs

@@ -93,7 +93,7 @@ impl Parse for Newtype {
                 }
                 impl<E: ::rustc_serialize::Encoder> ::rustc_serialize::Encodable<E> for #name {
                     fn encode(&self, e: &mut E) {
-                        e.emit_u32(self.private);
+                        e.emit_u32(self.as_u32());
                     }
                 }
             }
@@ -150,7 +150,7 @@ impl Parse for Newtype {
                         #[inline]
                         fn eq(l: &Option<Self>, r: &Option<Self>) -> bool {
                             if #max_val < u32::MAX {
-                                l.map(|i| i.private).unwrap_or(#max_val+1) == r.map(|i| i.private).unwrap_or(#max_val+1)
+                                l.map(|i| i.as_u32()).unwrap_or(#max_val+1) == r.map(|i| i.as_u32()).unwrap_or(#max_val+1)
                             } else {
                                 match (l, r) {
                                     (Some(l), Some(r)) => r == l,
@@ -174,7 +174,7 @@ impl Parse for Newtype {
             #[rustc_layout_scalar_valid_range_end(#max)]
             #[rustc_pass_by_value]
             #vis struct #name {
-                private: u32,
+                private_use_as_methods_instead: u32,
             }
 
             #(#consts)*
@@ -224,7 +224,7 @@ impl Parse for Newtype {
                 /// Prefer using `from_u32`.
                 #[inline]
                 #vis const unsafe fn from_u32_unchecked(value: u32) -> Self {
-                    Self { private: value }
+                    Self { private_use_as_methods_instead: value as _ }
                 }
 
                 /// Extracts the value of this index as a `usize`.
@@ -236,7 +236,7 @@ impl Parse for Newtype {
                 /// Extracts the value of this index as a `u32`.
                 #[inline]
                 #vis const fn as_u32(self) -> u32 {
-                    self.private
+                    self.private_use_as_methods_instead as u32
                 }
 
                 /// Extracts the value of this index as a `usize`.

compiler/rustc_type_ir/src/lib.rs

@@ -819,20 +819,20 @@ impl UniverseIndex {
     /// name the region `'a`, but that region was not nameable from
     /// `U` because it was not in scope there.
     pub fn next_universe(self) -> UniverseIndex {
-        UniverseIndex::from_u32(self.private.checked_add(1).unwrap())
+        UniverseIndex::from_u32(self.as_u32().checked_add(1).unwrap())
     }
 
     /// Returns `true` if `self` can name a name from `other` -- in other words,
     /// if the set of names in `self` is a superset of those in
     /// `other` (`self >= other`).
     pub fn can_name(self, other: UniverseIndex) -> bool {
-        self.private >= other.private
+        self >= other
     }
 
     /// Returns `true` if `self` cannot name some names from `other` -- in other
     /// words, if the set of names in `self` is a strict subset of
     /// those in `other` (`self < other`).
     pub fn cannot_name(self, other: UniverseIndex) -> bool {
-        self.private < other.private
+        self < other
     }
 }