Rollup merge of rust-lang#67480 - rossmacarthur:fix-41260-avoid-issue…

…-0-part-2, r=Centril

Require issue = "none" over issue = "0" in unstable attributes

These changes make the use of `issue = "none"` required in unstable attributes throughout the compiler.

Notes:
- rust-lang#66299 is now in beta so `issue = "none"` is accepted.
- The `tidy` tool now fails on `issue = "0"`.
- Tests that used `issue = "0"` were changed to use `issue = "none"`, except for _one_ that asserts `issue = "0"` can still be used.
- The compiler still allows `issue = "0"` because some submodules require it, this could be disallowed once these are updated.

Resolves rust-lang#41260

r? @varkor

src/liballoc/boxed.rs

@@ -476,7 +476,7 @@ impl<T: ?Sized> Box<T> {
         Box::into_unique(b).into()
     }
 
-    #[unstable(feature = "ptr_internals", issue = "0", reason = "use into_raw_non_null instead")]
+    #[unstable(feature = "ptr_internals", issue = "none", reason = "use into_raw_non_null instead")]
     #[inline]
     #[doc(hidden)]
     pub fn into_unique(b: Box<T>) -> Unique<T> {
@@ -830,7 +830,7 @@ impl From<Box<str>> for Box<[u8]> {
     }
 }
 
-#[unstable(feature = "boxed_slice_try_from", issue = "0")]
+#[unstable(feature = "boxed_slice_try_from", issue = "none")]
 impl<T, const N: usize> TryFrom<Box<[T]>> for Box<[T; N]>
 where
     [T; N]: LengthAtMost32,
@@ -946,7 +946,7 @@ impl<T: ?Sized> DerefMut for Box<T> {
     }
 }
 
-#[unstable(feature = "receiver_trait", issue = "0")]
+#[unstable(feature = "receiver_trait", issue = "none")]
 impl<T: ?Sized> Receiver for Box<T> {}
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -1040,7 +1040,7 @@ impl<A, F: Fn<A> + ?Sized> Fn<A> for Box<F> {
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Box<U>> for Box<T> {}
 
-#[unstable(feature = "dispatch_from_dyn", issue = "0")]
+#[unstable(feature = "dispatch_from_dyn", issue = "none")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<Box<U>> for Box<T> {}
 
 #[stable(feature = "boxed_slice_from_iter", since = "1.32.0")]

src/liballoc/collections/mod.rs

@@ -57,7 +57,7 @@ pub enum TryReserveError {
         layout: Layout,
 
         #[doc(hidden)]
-        #[unstable(feature = "container_error_extra", issue = "0", reason = "\
+        #[unstable(feature = "container_error_extra", issue = "none", reason = "\
             Enable exposing the allocator’s custom error value \
             if an associated type is added in the future: \
             https://github.com/rust-lang/wg-allocators/issues/23")]

src/liballoc/fmt.rs

@@ -514,7 +514,7 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 
-#[unstable(feature = "fmt_internals", issue = "0")]
+#[unstable(feature = "fmt_internals", issue = "none")]
 pub use core::fmt::rt;
 #[stable(feature = "fmt_flags_align", since = "1.28.0")]
 pub use core::fmt::Alignment;

src/liballoc/lib.rs

@@ -171,7 +171,7 @@ mod std {
 }
 
 #[doc(hidden)]
-#[unstable(feature = "liballoc_internals", issue = "0", reason = "implementation detail")]
+#[unstable(feature = "liballoc_internals", issue = "none", reason = "implementation detail")]
 pub mod __export {
     pub use core::format_args;
 }

src/liballoc/raw_vec.rs

@@ -1,4 +1,4 @@
-#![unstable(feature = "raw_vec_internals", reason = "implementation detail", issue = "0")]
+#![unstable(feature = "raw_vec_internals", reason = "implementation detail", issue = "none")]
 #![doc(hidden)]
 
 use core::cmp;

src/liballoc/rc.rs

@@ -291,7 +291,7 @@ impl<T: ?Sized> !marker::Sync for Rc<T> {}
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Rc<U>> for Rc<T> {}
 
-#[unstable(feature = "dispatch_from_dyn", issue = "0")]
+#[unstable(feature = "dispatch_from_dyn", issue = "none")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<Rc<U>> for Rc<T> {}
 
 impl<T: ?Sized> Rc<T> {
@@ -1090,7 +1090,7 @@ impl<T: ?Sized> Deref for Rc<T> {
     }
 }
 
-#[unstable(feature = "receiver_trait", issue = "0")]
+#[unstable(feature = "receiver_trait", issue = "none")]
 impl<T: ?Sized> Receiver for Rc<T> {}
 
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -1471,7 +1471,7 @@ impl<T> From<Vec<T>> for Rc<[T]> {
     }
 }
 
-#[unstable(feature = "boxed_slice_try_from", issue = "0")]
+#[unstable(feature = "boxed_slice_try_from", issue = "none")]
 impl<T, const N: usize> TryFrom<Rc<[T]>> for Rc<[T; N]>
 where
     [T; N]: LengthAtMost32,
@@ -1621,7 +1621,7 @@ impl<T: ?Sized> !marker::Sync for Weak<T> {}
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Weak<U>> for Weak<T> {}
 
-#[unstable(feature = "dispatch_from_dyn", issue = "0")]
+#[unstable(feature = "dispatch_from_dyn", issue = "none")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<Weak<U>> for Weak<T> {}
 
 impl<T> Weak<T> {

src/liballoc/sync.rs

@@ -206,7 +206,7 @@ unsafe impl<T: ?Sized + Sync + Send> Sync for Arc<T> {}
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Arc<U>> for Arc<T> {}
 
-#[unstable(feature = "dispatch_from_dyn", issue = "0")]
+#[unstable(feature = "dispatch_from_dyn", issue = "none")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<Arc<U>> for Arc<T> {}
 
 impl<T: ?Sized> Arc<T> {
@@ -263,7 +263,7 @@ unsafe impl<T: ?Sized + Sync + Send> Sync for Weak<T> {}
 
 #[unstable(feature = "coerce_unsized", issue = "27732")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<Weak<U>> for Weak<T> {}
-#[unstable(feature = "dispatch_from_dyn", issue = "0")]
+#[unstable(feature = "dispatch_from_dyn", issue = "none")]
 impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<Weak<U>> for Weak<T> {}
 
 #[stable(feature = "arc_weak", since = "1.4.0")]
@@ -993,7 +993,7 @@ impl<T: ?Sized> Deref for Arc<T> {
     }
 }
 
-#[unstable(feature = "receiver_trait", issue = "0")]
+#[unstable(feature = "receiver_trait", issue = "none")]
 impl<T: ?Sized> Receiver for Arc<T> {}
 
 impl<T: Clone> Arc<T> {
@@ -2032,7 +2032,7 @@ impl<T> From<Vec<T>> for Arc<[T]> {
     }
 }
 
-#[unstable(feature = "boxed_slice_try_from", issue = "0")]
+#[unstable(feature = "boxed_slice_try_from", issue = "none")]
 impl<T, const N: usize> TryFrom<Arc<[T]>> for Arc<[T; N]>
 where
     [T; N]: LengthAtMost32,

src/libcore/array/mod.rs

@@ -74,7 +74,7 @@ impl TryFromSliceError {
     #[unstable(feature = "array_error_internals",
            reason = "available through Error trait and this method should not \
                      be exposed publicly",
-           issue = "0")]
+           issue = "none")]
     #[inline]
     #[doc(hidden)]
     pub fn __description(&self) -> &str {
@@ -388,14 +388,14 @@ where
 #[rustc_on_unimplemented(
     message="arrays only have std trait implementations for lengths 0..=32",
 )]
-#[unstable(feature = "const_generic_impls_guard", issue = "0",
+#[unstable(feature = "const_generic_impls_guard", issue = "none",
     reason = "will never be stable, just a temporary step until const generics are stable")]
 pub trait LengthAtMost32 {}
 
 macro_rules! array_impls {
     ($($N:literal)+) => {
         $(
-            #[unstable(feature = "const_generic_impls_guard", issue = "0")]
+            #[unstable(feature = "const_generic_impls_guard", issue = "none")]
             impl<T> LengthAtMost32 for [T; $N] {}
         )+
     }

src/libcore/char/convert.rs

@@ -169,7 +169,7 @@ impl ParseCharError {
     #[unstable(
         feature = "char_error_internals",
         reason = "this method should not be available publicly",
-        issue = "0"
+        issue = "none"
     )]
     #[doc(hidden)]
     pub fn __description(&self) -> &str {

src/libcore/clone.rs

@@ -150,7 +150,7 @@ pub macro Clone($item:item) {
 #[unstable(
     feature = "derive_clone_copy",
     reason = "deriving hack, should not be public",
-    issue = "0"
+    issue = "none"
 )]
 pub struct AssertParamIsClone<T: Clone + ?Sized> {
     _field: crate::marker::PhantomData<T>,
@@ -160,7 +160,7 @@ pub struct AssertParamIsClone<T: Clone + ?Sized> {
 #[unstable(
     feature = "derive_clone_copy",
     reason = "deriving hack, should not be public",
-    issue = "0"
+    issue = "none"
 )]
 pub struct AssertParamIsCopy<T: Copy + ?Sized> {
     _field: crate::marker::PhantomData<T>,

src/libcore/cmp.rs

@@ -288,7 +288,7 @@ pub macro Eq($item:item) { /* compiler built-in */ }
 #[allow(missing_debug_implementations)]
 #[unstable(feature = "derive_eq",
            reason = "deriving hack, should not be public",
-           issue = "0")]
+           issue = "none")]
 pub struct AssertParamIsEq<T: Eq + ?Sized> { _field: crate::marker::PhantomData<T> }
 
 /// An `Ordering` is the result of a comparison between two values.

src/libcore/ffi.rs

@@ -38,14 +38,14 @@ pub enum c_void {
     #[unstable(
         feature = "c_void_variant",
         reason = "temporary implementation detail",
-        issue = "0"
+        issue = "none"
     )]
     #[doc(hidden)]
     __variant1,
     #[unstable(
         feature = "c_void_variant",
         reason = "temporary implementation detail",
-        issue = "0"
+        issue = "none"
     )]
     #[doc(hidden)]
     __variant2,

src/libcore/fmt/mod.rs

@@ -35,7 +35,7 @@ pub enum Alignment {
 #[stable(feature = "debug_builders", since = "1.2.0")]
 pub use self::builders::{DebugList, DebugMap, DebugSet, DebugStruct, DebugTuple};
 
-#[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "0")]
+#[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")]
 #[doc(hidden)]
 pub mod rt {
     pub mod v1;
@@ -259,7 +259,7 @@ struct Void {
 /// types, and then this struct is used to canonicalize arguments to one type.
 #[derive(Copy, Clone)]
 #[allow(missing_debug_implementations)]
-#[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "0")]
+#[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")]
 #[doc(hidden)]
 pub struct ArgumentV1<'a> {
     value: &'a Void,
@@ -273,13 +273,13 @@ impl<'a> ArgumentV1<'a> {
     }
 
     #[doc(hidden)]
-    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "0")]
+    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")]
     pub fn new<'b, T>(x: &'b T, f: fn(&T, &mut Formatter<'_>) -> Result) -> ArgumentV1<'b> {
         unsafe { ArgumentV1 { formatter: mem::transmute(f), value: mem::transmute(x) } }
     }
 
     #[doc(hidden)]
-    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "0")]
+    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")]
     pub fn from_usize(x: &usize) -> ArgumentV1<'_> {
         ArgumentV1::new(x, ArgumentV1::show_usize)
     }
@@ -309,7 +309,7 @@ impl<'a> Arguments<'a> {
     /// Arguments structure.
     #[doc(hidden)]
     #[inline]
-    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "0")]
+    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")]
     pub fn new_v1(pieces: &'a [&'a str], args: &'a [ArgumentV1<'a>]) -> Arguments<'a> {
         Arguments { pieces, fmt: None, args }
     }
@@ -322,7 +322,7 @@ impl<'a> Arguments<'a> {
     /// unsafety, but will ignore invalid .
     #[doc(hidden)]
     #[inline]
-    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "0")]
+    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")]
     pub fn new_v1_formatted(
         pieces: &'a [&'a str],
         args: &'a [ArgumentV1<'a>],
@@ -337,7 +337,7 @@ impl<'a> Arguments<'a> {
     /// when using `format!`. Note: this is neither the lower nor upper bound.
     #[doc(hidden)]
     #[inline]
-    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "0")]
+    #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")]
     pub fn estimated_capacity(&self) -> usize {
         let pieces_length: usize = self.pieces.iter().map(|x| x.len()).sum();
 

src/libcore/hash/mod.rs

@@ -90,7 +90,7 @@ use crate::marker;
 #[allow(deprecated)]
 pub use self::sip::SipHasher;
 
-#[unstable(feature = "hashmap_internals", issue = "0")]
+#[unstable(feature = "hashmap_internals", issue = "none")]
 #[allow(deprecated)]
 #[doc(hidden)]
 pub use self::sip::SipHasher13;

src/libcore/hash/sip.rs

@@ -15,7 +15,7 @@ use crate::ptr;
 /// (e.g., `collections::HashMap` uses it by default).
 ///
 /// See: <https://131002.net/siphash>
-#[unstable(feature = "hashmap_internals", issue = "0")]
+#[unstable(feature = "hashmap_internals", issue = "none")]
 #[rustc_deprecated(
     since = "1.13.0",
     reason = "use `std::collections::hash_map::DefaultHasher` instead"
@@ -29,7 +29,7 @@ pub struct SipHasher13 {
 /// An implementation of SipHash 2-4.
 ///
 /// See: <https://131002.net/siphash/>
-#[unstable(feature = "hashmap_internals", issue = "0")]
+#[unstable(feature = "hashmap_internals", issue = "none")]
 #[rustc_deprecated(
     since = "1.13.0",
     reason = "use `std::collections::hash_map::DefaultHasher` instead"
@@ -172,7 +172,7 @@ impl SipHasher {
 impl SipHasher13 {
     /// Creates a new `SipHasher13` with the two initial keys set to 0.
     #[inline]
-    #[unstable(feature = "hashmap_internals", issue = "0")]
+    #[unstable(feature = "hashmap_internals", issue = "none")]
     #[rustc_deprecated(
         since = "1.13.0",
         reason = "use `std::collections::hash_map::DefaultHasher` instead"
@@ -183,7 +183,7 @@ impl SipHasher13 {
 
     /// Creates a `SipHasher13` that is keyed off the provided keys.
     #[inline]
-    #[unstable(feature = "hashmap_internals", issue = "0")]
+    #[unstable(feature = "hashmap_internals", issue = "none")]
     #[rustc_deprecated(
         since = "1.13.0",
         reason = "use `std::collections::hash_map::DefaultHasher` instead"
@@ -264,7 +264,7 @@ impl super::Hasher for SipHasher {
     }
 }
 
-#[unstable(feature = "hashmap_internals", issue = "0")]
+#[unstable(feature = "hashmap_internals", issue = "none")]
 impl super::Hasher for SipHasher13 {
     #[inline]
     fn write(&mut self, msg: &[u8]) {

src/libcore/internal_macros.rs

@@ -77,7 +77,7 @@ macro_rules! forward_ref_op_assign {
 }
 
 /// Create a zero-size type similar to a closure type, but named.
-#[unstable(feature = "std_internals", issue = "0")]
+#[unstable(feature = "std_internals", issue = "none")]
 macro_rules! impl_fn_for_zst {
     ($(
         $( #[$attr: meta] )*

src/libcore/intrinsics.rs

@@ -33,7 +33,7 @@
             reason = "intrinsics are unlikely to ever be stabilized, instead \
                       they should be used through stabilized interfaces \
                       in the rest of the standard library",
-            issue = "0")]
+            issue = "none")]
 #![allow(missing_docs)]
 
 use crate::mem;
@@ -709,7 +709,7 @@ extern "rust-intrinsic" {
                reason = "intrinsics are unlikely to ever be stabilized, instead \
                          they should be used through stabilized interfaces \
                          in the rest of the standard library",
-               issue = "0")]
+               issue = "none")]
     #[rustc_deprecated(reason = "superseded by MaybeUninit, removal planned",
                        since = "1.38.0")]
     pub fn init<T>() -> T;
@@ -725,7 +725,7 @@ extern "rust-intrinsic" {
                reason = "intrinsics are unlikely to ever be stabilized, instead \
                          they should be used through stabilized interfaces \
                          in the rest of the standard library",
-               issue = "0")]
+               issue = "none")]
     #[rustc_deprecated(reason = "superseded by MaybeUninit, removal planned",
                        since = "1.38.0")]
     pub fn uninit<T>() -> T;

src/libcore/macros/mod.rs

@@ -799,7 +799,7 @@ pub(crate) mod builtin {
     /// Same as `format_args`, but adds a newline in the end.
     #[unstable(
         feature = "format_args_nl",
-        issue = "0",
+        issue = "none",
         reason = "`format_args_nl` is only for internal \
                   language use and is subject to change"
     )]