diff --git a/compiler/rustc_builtin_macros/src/deriving/smart_ptr.rs b/compiler/rustc_builtin_macros/src/deriving/smart_ptr.rs
index 02555bd799c42..827a60f9f9609 100644
--- a/compiler/rustc_builtin_macros/src/deriving/smart_ptr.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/smart_ptr.rs
@@ -1,5 +1,3 @@
-use std::mem::swap;
-
use ast::ptr::P;
use ast::HasAttrs;
use rustc_ast::mut_visit::MutVisitor;
@@ -154,13 +152,28 @@ pub fn expand_deriving_smart_ptr(
{
let pointee = &mut impl_generics.params[pointee_param_idx];
self_bounds = pointee.bounds.clone();
+ if !contains_maybe_sized_bound(&self_bounds)
+ && !contains_maybe_sized_bound_on_pointee(
+ &generics.where_clause.predicates,
+ pointee_ty_ident.name,
+ )
+ {
+ cx.dcx()
+ .struct_span_err(
+ pointee_ty_ident.span,
+ format!(
+ "`derive(SmartPointer)` requires {} to be marked `?Sized`",
+ pointee_ty_ident.name
+ ),
+ )
+ .emit();
+ return;
+ }
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));
- let mut attrs = thin_vec![];
- swap(&mut pointee.attrs, &mut attrs);
// Drop `#[pointee]` attribute since it should not be recognized outside `derive(SmartPointer)`
- pointee.attrs = attrs.into_iter().filter(|attr| !attr.has_name(sym::pointee)).collect();
+ pointee.attrs.retain(|attr| !attr.has_name(sym::pointee));
}
// # Rewrite generic parameter bounds
@@ -218,23 +231,6 @@ pub fn expand_deriving_smart_ptr(
//
// We now insert `__S` with the missing bounds marked with (*) above.
// We should also write the bounds from `#[pointee]` to `__S` as required by `Unsize<__S>`.
- let sized = cx.path_global(span, path!(span, core::marker::Sized));
- // For some reason, we are not allowed to write `?Sized` bound twice like `__S: ?Sized + ?Sized`.
- if !contains_maybe_sized_bound(&self_bounds)
- && !contains_maybe_sized_bound_on_pointee(
- &generics.where_clause.predicates,
- pointee_ty_ident.name,
- )
- {
- self_bounds.push(GenericBound::Trait(
- cx.poly_trait_ref(span, sized),
- TraitBoundModifiers {
- polarity: ast::BoundPolarity::Maybe(span),
- constness: ast::BoundConstness::Never,
- asyncness: ast::BoundAsyncness::Normal,
- },
- ));
- }
{
let mut substitution =
TypeSubstitution { from_name: pointee_ty_ident.name, to_ty: &s_ty, rewritten: false };
diff --git a/tests/ui/deriving/deriving-smart-pointer-neg.rs b/tests/ui/deriving/deriving-smart-pointer-neg.rs
index bfb4e86b39601..04f52a154fe42 100644
--- a/tests/ui/deriving/deriving-smart-pointer-neg.rs
+++ b/tests/ui/deriving/deriving-smart-pointer-neg.rs
@@ -1,5 +1,6 @@
#![feature(derive_smart_pointer, arbitrary_self_types)]
+extern crate core;
use std::marker::SmartPointer;
#[derive(SmartPointer)]
@@ -35,6 +36,13 @@ struct NotTransparent<'a, #[pointee] T: ?Sized> {
ptr: &'a T,
}
+#[derive(SmartPointer)]
+#[repr(transparent)]
+struct NoMaybeSized<'a, #[pointee] T> {
+ //~^ ERROR: `derive(SmartPointer)` requires T to be marked `?Sized`
+ ptr: &'a T,
+}
+
// However, reordering attributes should work nevertheless.
#[repr(transparent)]
#[derive(SmartPointer)]
@@ -42,4 +50,26 @@ struct ThisIsAPossibleSmartPointer<'a, #[pointee] T: ?Sized> {
ptr: &'a T,
}
+// Also, these paths to Sized should work
+#[derive(SmartPointer)]
+#[repr(transparent)]
+struct StdSized<'a, #[pointee] T: ?std::marker::Sized> {
+ ptr: &'a T,
+}
+#[derive(SmartPointer)]
+#[repr(transparent)]
+struct CoreSized<'a, #[pointee] T: ?core::marker::Sized> {
+ ptr: &'a T,
+}
+#[derive(SmartPointer)]
+#[repr(transparent)]
+struct GlobalStdSized<'a, #[pointee] T: ?::std::marker::Sized> {
+ ptr: &'a T,
+}
+#[derive(SmartPointer)]
+#[repr(transparent)]
+struct GlobalCoreSized<'a, #[pointee] T: ?::core::marker::Sized> {
+ ptr: &'a T,
+}
+
fn main() {}
diff --git a/tests/ui/deriving/deriving-smart-pointer-neg.stderr b/tests/ui/deriving/deriving-smart-pointer-neg.stderr
index d994a6ee376b0..8b0f91d41fb88 100644
--- a/tests/ui/deriving/deriving-smart-pointer-neg.stderr
+++ b/tests/ui/deriving/deriving-smart-pointer-neg.stderr
@@ -1,5 +1,5 @@
error: `SmartPointer` can only be derived on `struct`s with `#[repr(transparent)]`
- --> $DIR/deriving-smart-pointer-neg.rs:5:10
+ --> $DIR/deriving-smart-pointer-neg.rs:6:10
|
LL | #[derive(SmartPointer)]
| ^^^^^^^^^^^^
@@ -7,7 +7,7 @@ LL | #[derive(SmartPointer)]
= note: this error originates in the derive macro `SmartPointer` (in Nightly builds, run with -Z macro-backtrace for more info)
error: At least one generic type should be designated as `#[pointee]` in order to derive `SmartPointer` traits
- --> $DIR/deriving-smart-pointer-neg.rs:11:10
+ --> $DIR/deriving-smart-pointer-neg.rs:12:10
|
LL | #[derive(SmartPointer)]
| ^^^^^^^^^^^^
@@ -15,7 +15,7 @@ LL | #[derive(SmartPointer)]
= note: this error originates in the derive macro `SmartPointer` (in Nightly builds, run with -Z macro-backtrace for more info)
error: `SmartPointer` can only be derived on `struct`s with at least one field
- --> $DIR/deriving-smart-pointer-neg.rs:18:10
+ --> $DIR/deriving-smart-pointer-neg.rs:19:10
|
LL | #[derive(SmartPointer)]
| ^^^^^^^^^^^^
@@ -23,7 +23,7 @@ LL | #[derive(SmartPointer)]
= note: this error originates in the derive macro `SmartPointer` (in Nightly builds, run with -Z macro-backtrace for more info)
error: `SmartPointer` can only be derived on `struct`s with at least one field
- --> $DIR/deriving-smart-pointer-neg.rs:25:10
+ --> $DIR/deriving-smart-pointer-neg.rs:26:10
|
LL | #[derive(SmartPointer)]
| ^^^^^^^^^^^^
@@ -31,15 +31,21 @@ LL | #[derive(SmartPointer)]
= note: this error originates in the derive macro `SmartPointer` (in Nightly builds, run with -Z macro-backtrace for more info)
error: `SmartPointer` can only be derived on `struct`s with `#[repr(transparent)]`
- --> $DIR/deriving-smart-pointer-neg.rs:32:10
+ --> $DIR/deriving-smart-pointer-neg.rs:33:10
|
LL | #[derive(SmartPointer)]
| ^^^^^^^^^^^^
|
= note: this error originates in the derive macro `SmartPointer` (in Nightly builds, run with -Z macro-backtrace for more info)
+error: `derive(SmartPointer)` requires T to be marked `?Sized`
+ --> $DIR/deriving-smart-pointer-neg.rs:41:36
+ |
+LL | struct NoMaybeSized<'a, #[pointee] T> {
+ | ^
+
error[E0392]: lifetime parameter `'a` is never used
- --> $DIR/deriving-smart-pointer-neg.rs:21:16
+ --> $DIR/deriving-smart-pointer-neg.rs:22:16
|
LL | struct NoField<'a, #[pointee] T: ?Sized> {}
| ^^ unused lifetime parameter
@@ -47,7 +53,7 @@ LL | struct NoField<'a, #[pointee] T: ?Sized> {}
= help: consider removing `'a`, referring to it in a field, or using a marker such as `PhantomData`
error[E0392]: type parameter `T` is never used
- --> $DIR/deriving-smart-pointer-neg.rs:21:31
+ --> $DIR/deriving-smart-pointer-neg.rs:22:31
|
LL | struct NoField<'a, #[pointee] T: ?Sized> {}
| ^ unused type parameter
@@ -55,7 +61,7 @@ LL | struct NoField<'a, #[pointee] T: ?Sized> {}
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
error[E0392]: lifetime parameter `'a` is never used
- --> $DIR/deriving-smart-pointer-neg.rs:28:20
+ --> $DIR/deriving-smart-pointer-neg.rs:29:20
|
LL | struct NoFieldUnit<'a, #[pointee] T: ?Sized>();
| ^^ unused lifetime parameter
@@ -63,13 +69,13 @@ LL | struct NoFieldUnit<'a, #[pointee] T: ?Sized>();
= help: consider removing `'a`, referring to it in a field, or using a marker such as `PhantomData`
error[E0392]: type parameter `T` is never used
- --> $DIR/deriving-smart-pointer-neg.rs:28:35
+ --> $DIR/deriving-smart-pointer-neg.rs:29:35
|
LL | struct NoFieldUnit<'a, #[pointee] T: ?Sized>();
| ^ unused type parameter
|
= help: consider removing `T`, referring to it in a field, or using a marker such as `PhantomData`
-error: aborting due to 9 previous errors
+error: aborting due to 10 previous errors
For more information about this error, try `rustc --explain E0392`.