Auto merge of #131284 - dingxiangfei2009:rename-smart-ptr-to-coerce-referent, r=compiler-errors

Rename macro `SmartPointer` to `CoercePointee`

As per resolution #129104 we will rename the macro to better reflect the technical specification of the feature and clarify the communication.

- `SmartPointer` is renamed to `CoerceReferent`
- `#[pointee]` attribute is renamed to `#[referent]`
- `#![feature(derive_smart_pointer)]` gate is renamed to `#![feature(derive_coerce_referent)]`.
- Any mention of `SmartPointer` in the file names are renamed accordingly.

r? `@compiler-errors`

cc `@nikomatsakis` `@Darksonn`

Author: bors

compiler/rustc_builtin_macros/src/deriving/smart_ptr.rs compiler/rustc_builtin_macros/src/deriving/coerce_pointee.rs

@@ -19,7 +19,7 @@ macro_rules! path {
     ($span:expr, $($part:ident)::*) => { vec![$(Ident::new(sym::$part, $span),)*] }
 }
 
-pub(crate) fn expand_deriving_smart_ptr(
+pub(crate) fn expand_deriving_coerce_pointee(
     cx: &ExtCtxt<'_>,
     span: Span,
     _mitem: &MetaItem,
@@ -41,7 +41,7 @@ pub(crate) fn expand_deriving_smart_ptr(
             cx.dcx()
                 .struct_span_err(
                     span,
-                    "`SmartPointer` can only be derived on `struct`s with `#[repr(transparent)]`",
+                    "`CoercePointee` can only be derived on `struct`s with `#[repr(transparent)]`",
                 )
                 .emit();
             return;
@@ -54,7 +54,7 @@ pub(crate) fn expand_deriving_smart_ptr(
             cx.dcx()
                 .struct_span_err(
                     span,
-                    "`SmartPointer` can only be derived on `struct`s with at least one field",
+                    "`CoercePointee` can only be derived on `struct`s with at least one field",
                 )
                 .emit();
             return;
@@ -64,7 +64,7 @@ pub(crate) fn expand_deriving_smart_ptr(
         cx.dcx()
             .struct_span_err(
                 span,
-                "`SmartPointer` can only be derived on `struct`s with `#[repr(transparent)]`",
+                "`CoercePointee` can only be derived on `struct`s with `#[repr(transparent)]`",
             )
             .emit();
         return;
@@ -94,10 +94,10 @@ pub(crate) fn expand_deriving_smart_ptr(
         .collect();
 
     let pointee_param_idx = if type_params.is_empty() {
-        // `#[derive(SmartPointer)]` requires at least one generic type on the target `struct`
+        // `#[derive(CoercePointee)]` requires at least one generic type on the target `struct`
         cx.dcx().struct_span_err(
             span,
-            "`SmartPointer` can only be derived on `struct`s that are generic over at least one type",
+            "`CoercePointee` can only be derived on `struct`s that are generic over at least one type",
         ).emit();
         return;
     } else if type_params.len() == 1 {
@@ -113,15 +113,15 @@ pub(crate) fn expand_deriving_smart_ptr(
             (None, _) => {
                 cx.dcx().struct_span_err(
                     span,
-                    "exactly one generic type parameter must be marked as #[pointee] to derive SmartPointer traits",
+                    "exactly one generic type parameter must be marked as #[pointee] to derive CoercePointee traits",
                 ).emit();
                 return;
             }
             (Some((_, one)), Some((_, another))) => {
                 cx.dcx()
                     .struct_span_err(
                         vec![one, another],
-                        "only one type parameter can be marked as `#[pointee]` when deriving SmartPointer traits",
+                        "only one type parameter can be marked as `#[pointee]` when deriving CoercePointee traits",
                     )
                     .emit();
                 return;
@@ -185,7 +185,7 @@ pub(crate) fn expand_deriving_smart_ptr(
                 .struct_span_err(
                     pointee_ty_ident.span,
                     format!(
-                        "`derive(SmartPointer)` requires {} to be marked `?Sized`",
+                        "`derive(CoercePointee)` requires {} to be marked `?Sized`",
                         pointee_ty_ident.name
                     ),
                 )
@@ -195,7 +195,7 @@ pub(crate) fn expand_deriving_smart_ptr(
         let arg = GenericArg::Type(s_ty.clone());
         let unsize = cx.path_all(span, true, path!(span, core::marker::Unsize), vec![arg]);
         pointee.bounds.push(cx.trait_bound(unsize, false));
-        // Drop `#[pointee]` attribute since it should not be recognized outside `derive(SmartPointer)`
+        // Drop `#[pointee]` attribute since it should not be recognized outside `derive(CoercePointee)`
         pointee.attrs.retain(|attr| !attr.has_name(sym::pointee));
     }
 

compiler/rustc_builtin_macros/src/deriving/mod.rs

@@ -22,12 +22,12 @@ macro path_std($($x:tt)*) {
 
 pub(crate) mod bounds;
 pub(crate) mod clone;
+pub(crate) mod coerce_pointee;
 pub(crate) mod debug;
 pub(crate) mod decodable;
 pub(crate) mod default;
 pub(crate) mod encodable;
 pub(crate) mod hash;
-pub(crate) mod smart_ptr;
 
 #[path = "cmp/eq.rs"]
 pub(crate) mod eq;

compiler/rustc_builtin_macros/src/lib.rs

@@ -133,7 +133,7 @@ pub fn register_builtin_macros(resolver: &mut dyn ResolverExpand) {
         PartialOrd: partial_ord::expand_deriving_partial_ord,
         RustcDecodable: decodable::expand_deriving_rustc_decodable,
         RustcEncodable: encodable::expand_deriving_rustc_encodable,
-        SmartPointer: smart_ptr::expand_deriving_smart_ptr,
+        CoercePointee: coerce_pointee::expand_deriving_coerce_pointee,
     }
 
     let client = proc_macro::bridge::client::Client::expand1(proc_macro::quote);

compiler/rustc_feature/src/removed.rs

@@ -85,6 +85,8 @@ declare_features! (
     /// Allows default type parameters to influence type inference.
     (removed, default_type_parameter_fallback, "1.82.0", Some(27336),
      Some("never properly implemented; requires significant design work")),
+    /// Allows deriving traits as per `SmartPointer` specification
+    (removed, derive_smart_pointer, "1.79.0", Some(123430), Some("replaced by `CoercePointee`")),
     /// Allows using `#[doc(keyword = "...")]`.
     (removed, doc_keyword, "1.28.0", Some(51315),
      Some("merged into `#![feature(rustdoc_internals)]`")),

compiler/rustc_feature/src/unstable.rs

@@ -450,8 +450,6 @@ declare_features! (
     (unstable, deprecated_suggestion, "1.61.0", Some(94785)),
     /// Allows deref patterns.
     (incomplete, deref_patterns, "1.79.0", Some(87121)),
-    /// Allows deriving `SmartPointer` traits
-    (unstable, derive_smart_pointer, "1.79.0", Some(123430)),
     /// Controls errors in trait implementations.
     (unstable, do_not_recommend, "1.67.0", Some(51992)),
     /// Tells rustdoc to automatically generate `#[doc(cfg(...))]`.

compiler/rustc_passes/src/check_attr.rs

@@ -262,7 +262,7 @@ impl<'tcx> CheckAttrVisitor<'tcx> {
                     | sym::cfg_attr
                     // need to be fixed
                     | sym::cfi_encoding // FIXME(cfi_encoding)
-                    | sym::pointee // FIXME(derive_smart_pointer)
+                    | sym::pointee // FIXME(derive_coerce_pointee)
                     | sym::omit_gdb_pretty_printer_section // FIXME(omit_gdb_pretty_printer_section)
                     | sym::used // handled elsewhere to restrict to static items
                     | sym::repr // handled elsewhere to restrict to type decls items

compiler/rustc_span/src/symbol.rs

@@ -174,6 +174,7 @@ symbols! {
         Center,
         Cleanup,
         Clone,
+        CoercePointee,
         CoerceUnsized,
         Command,
         ConstParamTy,
@@ -307,7 +308,6 @@ symbols! {
         Sized,
         SliceIndex,
         SliceIter,
-        SmartPointer,
         Some,
         SpanCtxt,
         String,
@@ -732,6 +732,7 @@ symbols! {
         deref_pure,
         deref_target,
         derive,
+        derive_coerce_pointee,
         derive_const,
         derive_default_enum,
         derive_smart_pointer,

library/core/src/marker.rs

@@ -1063,9 +1063,10 @@ pub trait FnPtr: Copy + Clone {
 }
 
 /// Derive macro generating impls of traits related to smart pointers.
-#[rustc_builtin_macro(SmartPointer, attributes(pointee))]
+#[rustc_builtin_macro(CoercePointee, attributes(pointee))]
 #[allow_internal_unstable(dispatch_from_dyn, coerce_unsized, unsize)]
-#[unstable(feature = "derive_smart_pointer", issue = "123430")]
-pub macro SmartPointer($item:item) {
+#[unstable(feature = "derive_coerce_pointee", issue = "123430")]
+#[cfg(not(bootstrap))]
+pub macro CoercePointee($item:item) {
     /* compiler built-in */
 }

tests/ui/deriving/auxiliary/another-proc-macro.rs

@@ -6,7 +6,7 @@
 
 extern crate proc_macro;
 
-use proc_macro::{quote, TokenStream};
+use proc_macro::{TokenStream, quote};
 
 #[proc_macro_derive(AnotherMacro, attributes(pointee))]
 pub fn derive(_input: TokenStream) -> TokenStream {

tests/ui/deriving/built-in-proc-macro-scope.rs

@@ -2,14 +2,14 @@
 //@ aux-build: another-proc-macro.rs
 //@ compile-flags: -Zunpretty=expanded
 
-#![feature(derive_smart_pointer)]
+#![feature(derive_coerce_pointee)]
 
 #[macro_use]
 extern crate another_proc_macro;
 
-use another_proc_macro::{pointee, AnotherMacro};
+use another_proc_macro::{AnotherMacro, pointee};
 
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 #[repr(transparent)]
 pub struct Ptr<'a, #[pointee] T: ?Sized> {
     data: &'a mut T,

tests/ui/deriving/built-in-proc-macro-scope.stdout

@@ -4,7 +4,7 @@
 //@ aux-build: another-proc-macro.rs
 //@ compile-flags: -Zunpretty=expanded
 
-#![feature(derive_smart_pointer)]
+#![feature(derive_coerce_pointee)]
 #[prelude_import]
 use ::std::prelude::rust_2015::*;
 #[macro_use]
@@ -13,7 +13,7 @@ extern crate std;
 #[macro_use]
 extern crate another_proc_macro;
 
-use another_proc_macro::{pointee, AnotherMacro};
+use another_proc_macro::{AnotherMacro, pointee};
 
 #[repr(transparent)]
 pub struct Ptr<'a, #[pointee] T: ?Sized> {

tests/ui/deriving/smart-pointer-bounds-issue-127647.rs tests/ui/deriving/coerce-pointee-bounds-issue-127647.rs

@@ -1,8 +1,8 @@
 //@ check-pass
 
-#![feature(derive_smart_pointer)]
+#![feature(derive_coerce_pointee)]
 
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 #[repr(transparent)]
 pub struct Ptr<'a, #[pointee] T: OnDrop + ?Sized, X> {
     data: &'a mut T,
@@ -13,7 +13,7 @@ pub trait OnDrop {
     fn on_drop(&mut self);
 }
 
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 #[repr(transparent)]
 pub struct Ptr2<'a, #[pointee] T: ?Sized, X>
 where
@@ -25,7 +25,7 @@ where
 
 pub trait MyTrait<T: ?Sized> {}
 
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 #[repr(transparent)]
 pub struct Ptr3<'a, #[pointee] T: ?Sized, X>
 where
@@ -35,14 +35,14 @@ where
     x: core::marker::PhantomData<X>,
 }
 
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 #[repr(transparent)]
 pub struct Ptr4<'a, #[pointee] T: MyTrait<T> + ?Sized, X> {
     data: &'a mut T,
     x: core::marker::PhantomData<X>,
 }
 
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 #[repr(transparent)]
 pub struct Ptr5<'a, #[pointee] T: ?Sized, X>
 where
@@ -56,7 +56,7 @@ where
 pub struct Ptr5Companion<T: ?Sized>(core::marker::PhantomData<T>);
 pub struct Ptr5Companion2;
 
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 #[repr(transparent)]
 pub struct Ptr6<'a, #[pointee] T: ?Sized, X: MyTrait<T> = (), const PARAM: usize = 0> {
     data: &'a mut T,
@@ -65,7 +65,7 @@ pub struct Ptr6<'a, #[pointee] T: ?Sized, X: MyTrait<T> = (), const PARAM: usize
 
 // a reduced example from https://lore.kernel.org/all/20240402-linked-list-v1-1-b1c59ba7ae3b@google.com/
 #[repr(transparent)]
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 pub struct ListArc<#[pointee] T, const ID: u64 = 0>
 where
     T: ListArcSafe<ID> + ?Sized,

tests/ui/deriving/deriving-smart-pointer-expanded.rs tests/ui/deriving/deriving-coerce-pointee-expanded.rs

@@ -1,17 +1,17 @@
 //@ check-pass
 //@ compile-flags: -Zunpretty=expanded
-#![feature(derive_smart_pointer)]
-use std::marker::SmartPointer;
+#![feature(derive_coerce_pointee)]
+use std::marker::CoercePointee;
 
 pub trait MyTrait<T: ?Sized> {}
 
-#[derive(SmartPointer)]
+#[derive(CoercePointee)]
 #[repr(transparent)]
 struct MyPointer<'a, #[pointee] T: ?Sized> {
     ptr: &'a T,
 }
 
-#[derive(core::marker::SmartPointer)]
+#[derive(core::marker::CoercePointee)]
 #[repr(transparent)]
 pub struct MyPointer2<'a, Y, Z: MyTrait<T>, #[pointee] T: ?Sized + MyTrait<T>, X: MyTrait<T> = ()>
 where
@@ -21,7 +21,7 @@ where
     x: core::marker::PhantomData<X>,
 }
 
-#[derive(SmartPointer)]
+#[derive(CoercePointee)]
 #[repr(transparent)]
 struct MyPointerWithoutPointee<'a, T: ?Sized> {
     ptr: &'a T,

tests/ui/deriving/deriving-smart-pointer-expanded.stdout tests/ui/deriving/deriving-coerce-pointee-expanded.stdout

@@ -2,12 +2,12 @@
 #![no_std]
 //@ check-pass
 //@ compile-flags: -Zunpretty=expanded
-#![feature(derive_smart_pointer)]
+#![feature(derive_coerce_pointee)]
 #[prelude_import]
 use ::std::prelude::rust_2015::*;
 #[macro_use]
 extern crate std;
-use std::marker::SmartPointer;
+use std::marker::CoercePointee;
 
 pub trait MyTrait<T: ?Sized> {}