Rollup merge of #108909 - spastorino:new-rpitit-7, r=compiler-errors

Fix object safety checks for new RPITITs

This one goes on top of #108869

r? `@compiler-errors`

11 files changed, 134 insertions, 15 deletions

diff --git a/compiler/rustc_hir_analysis/src/astconv/mod.rs b/compiler/rustc_hir_analysis/src/astconv/mod.rs
index 3cd4c4afe86..f830269b45d 100644
--- a/compiler/rustc_hir_analysis/src/astconv/mod.rs
+++ b/compiler/rustc_hir_analysis/src/astconv/mod.rs
@@ -1440,6 +1440,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                             tcx.associated_items(pred.def_id())
                                 .in_definition_order()
                                 .filter(|item| item.kind == ty::AssocKind::Type)
+                                .filter(|item| tcx.opt_rpitit_info(item.def_id).is_none())
                                 .map(|item| item.def_id),
                         );
                     }
diff --git a/compiler/rustc_trait_selection/src/traits/object_safety.rs b/compiler/rustc_trait_selection/src/traits/object_safety.rs
index 4eacb5211f7..a5def4151bf 100644
--- a/compiler/rustc_trait_selection/src/traits/object_safety.rs
+++ b/compiler/rustc_trait_selection/src/traits/object_safety.rs
@@ -13,7 +13,6 @@ use super::{elaborate_predicates, elaborate_trait_ref};
 use crate::infer::TyCtxtInferExt;
 use crate::traits::query::evaluate_obligation::InferCtxtExt;
 use crate::traits::{self, Obligation, ObligationCause};
-use hir::def::DefKind;
 use rustc_errors::{DelayDm, FatalError, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
@@ -157,6 +156,7 @@ fn object_safety_violations_for_trait(
                 .in_definition_order()
                 .filter(|item| item.kind == ty::AssocKind::Type)
                 .filter(|item| !tcx.generics_of(item.def_id).params.is_empty())
+                .filter(|item| tcx.opt_rpitit_info(item.def_id).is_none())
                 .map(|item| {
                     let ident = item.ident(tcx);
                     ObjectSafetyViolation::GAT(ident.name, ident.span)
@@ -854,7 +854,7 @@ fn contains_illegal_self_type_reference<'tcx, T: TypeVisitable<TyCtxt<'tcx>>>(
                     }
                 }
                 ty::Alias(ty::Projection, ref data)
-                    if self.tcx.def_kind(data.def_id) == DefKind::ImplTraitPlaceholder =>
+                    if self.tcx.is_impl_trait_in_trait(data.def_id) =>
                 {
                     // We'll deny these later in their own pass
                     ControlFlow::Continue(())
@@ -921,7 +921,7 @@ pub fn contains_illegal_impl_trait_in_trait<'tcx>(
     ty.skip_binder().walk().find_map(|arg| {
         if let ty::GenericArgKind::Type(ty) = arg.unpack()
             && let ty::Alias(ty::Projection, proj) = ty.kind()
-            && tcx.def_kind(proj.def_id) == DefKind::ImplTraitPlaceholder
+            && tcx.is_impl_trait_in_trait(proj.def_id)
         {
             Some(MethodViolationCode::ReferencesImplTraitInTrait(tcx.def_span(proj.def_id)))
         } else {
diff --git a/tests/ui/async-await/in-trait/object-safety.stderr b/tests/ui/async-await/in-trait/object-safety.current.stderr
index 0b318f71f39..90e049a9960 100644
--- a/tests/ui/async-await/in-trait/object-safety.stderr
+++ b/tests/ui/async-await/in-trait/object-safety.current.stderr
@@ -1,5 +1,5 @@
 warning: the feature `async_fn_in_trait` is incomplete and may not be safe to use and/or cause compiler crashes
-  --> $DIR/object-safety.rs:3:12
+  --> $DIR/object-safety.rs:5:12
    |
 LL | #![feature(async_fn_in_trait)]
    |            ^^^^^^^^^^^^^^^^^
@@ -8,13 +8,13 @@ LL | #![feature(async_fn_in_trait)]
    = note: `#[warn(incomplete_features)]` on by default
 
 error[E0038]: the trait `Foo` cannot be made into an object
-  --> $DIR/object-safety.rs:11:12
+  --> $DIR/object-safety.rs:13:12
    |
 LL |     let x: &dyn Foo = todo!();
    |            ^^^^^^^^ `Foo` cannot be made into an object
    |
 note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
-  --> $DIR/object-safety.rs:7:14
+  --> $DIR/object-safety.rs:9:14
    |
 LL | trait Foo {
    |       --- this trait cannot be made into an object...
diff --git a/tests/ui/async-await/in-trait/object-safety.next.stderr b/tests/ui/async-await/in-trait/object-safety.next.stderr
new file mode 100644
index 00000000000..90e049a9960
--- /dev/null
+++ b/tests/ui/async-await/in-trait/object-safety.next.stderr
@@ -0,0 +1,27 @@
+warning: the feature `async_fn_in_trait` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/object-safety.rs:5:12
+   |
+LL | #![feature(async_fn_in_trait)]
+   |            ^^^^^^^^^^^^^^^^^
+   |
+   = note: see issue #91611 <https://github.com/rust-lang/rust/issues/91611> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error[E0038]: the trait `Foo` cannot be made into an object
+  --> $DIR/object-safety.rs:13:12
+   |
+LL |     let x: &dyn Foo = todo!();
+   |            ^^^^^^^^ `Foo` cannot be made into an object
+   |
+note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
+  --> $DIR/object-safety.rs:9:14
+   |
+LL | trait Foo {
+   |       --- this trait cannot be made into an object...
+LL |     async fn foo(&self);
+   |              ^^^ ...because method `foo` is `async`
+   = help: consider moving `foo` to another trait
+
+error: aborting due to previous error; 1 warning emitted
+
+For more information about this error, try `rustc --explain E0038`.
diff --git a/tests/ui/async-await/in-trait/object-safety.rs b/tests/ui/async-await/in-trait/object-safety.rs
index a8bc35f7e0c..f67286a20a2 100644
--- a/tests/ui/async-await/in-trait/object-safety.rs
+++ b/tests/ui/async-await/in-trait/object-safety.rs
@@ -1,4 +1,6 @@
 // edition:2021
+// [next] compile-flags: -Zlower-impl-trait-in-trait-to-assoc-ty
+// revisions: current next
 
 #![feature(async_fn_in_trait)]
 //~^ WARN the feature `async_fn_in_trait` is incomplete and may not be safe to use and/or cause compiler crashes
diff --git a/tests/ui/impl-trait/in-trait/issue-102140.stderr b/tests/ui/impl-trait/in-trait/issue-102140.current.stderr
index 18bb63745d7..7aa7880e258 100644
--- a/tests/ui/impl-trait/in-trait/issue-102140.stderr
+++ b/tests/ui/impl-trait/in-trait/issue-102140.current.stderr
@@ -1,5 +1,5 @@
 error[E0277]: the trait bound `&dyn MyTrait: MyTrait` is not satisfied
-  --> $DIR/issue-102140.rs:23:22
+  --> $DIR/issue-102140.rs:26:22
    |
 LL |         MyTrait::foo(&self)
    |         ------------ ^^^^^ the trait `MyTrait` is not implemented for `&dyn MyTrait`
@@ -13,7 +13,7 @@ LL +         MyTrait::foo(self)
    |
 
 error[E0277]: the trait bound `&dyn MyTrait: MyTrait` is not satisfied
-  --> $DIR/issue-102140.rs:23:9
+  --> $DIR/issue-102140.rs:26:9
    |
 LL |         MyTrait::foo(&self)
    |         ^^^^^^^^^^^^^^^^^^^ the trait `MyTrait` is not implemented for `&dyn MyTrait`
@@ -21,7 +21,7 @@ LL |         MyTrait::foo(&self)
    = help: the trait `MyTrait` is implemented for `Outer`
 
 error[E0277]: the trait bound `&dyn MyTrait: MyTrait` is not satisfied
-  --> $DIR/issue-102140.rs:23:9
+  --> $DIR/issue-102140.rs:26:9
    |
 LL |         MyTrait::foo(&self)
    |         ^^^^^^^^^^^^ the trait `MyTrait` is not implemented for `&dyn MyTrait`
diff --git a/tests/ui/impl-trait/in-trait/issue-102140.next.stderr b/tests/ui/impl-trait/in-trait/issue-102140.next.stderr
new file mode 100644
index 00000000000..7aa7880e258
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/issue-102140.next.stderr
@@ -0,0 +1,33 @@
+error[E0277]: the trait bound `&dyn MyTrait: MyTrait` is not satisfied
+  --> $DIR/issue-102140.rs:26:22
+   |
+LL |         MyTrait::foo(&self)
+   |         ------------ ^^^^^ the trait `MyTrait` is not implemented for `&dyn MyTrait`
+   |         |
+   |         required by a bound introduced by this call
+   |
+help: consider removing the leading `&`-reference
+   |
+LL -         MyTrait::foo(&self)
+LL +         MyTrait::foo(self)
+   |
+
+error[E0277]: the trait bound `&dyn MyTrait: MyTrait` is not satisfied
+  --> $DIR/issue-102140.rs:26:9
+   |
+LL |         MyTrait::foo(&self)
+   |         ^^^^^^^^^^^^^^^^^^^ the trait `MyTrait` is not implemented for `&dyn MyTrait`
+   |
+   = help: the trait `MyTrait` is implemented for `Outer`
+
+error[E0277]: the trait bound `&dyn MyTrait: MyTrait` is not satisfied
+  --> $DIR/issue-102140.rs:26:9
+   |
+LL |         MyTrait::foo(&self)
+   |         ^^^^^^^^^^^^ the trait `MyTrait` is not implemented for `&dyn MyTrait`
+   |
+   = help: the trait `MyTrait` is implemented for `Outer`
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/impl-trait/in-trait/issue-102140.rs b/tests/ui/impl-trait/in-trait/issue-102140.rs
index be1e012acb1..4dcac4f5b0e 100644
--- a/tests/ui/impl-trait/in-trait/issue-102140.rs
+++ b/tests/ui/impl-trait/in-trait/issue-102140.rs
@@ -1,3 +1,6 @@
+// [next] compile-flags: -Zlower-impl-trait-in-trait-to-assoc-ty
+// revisions: current next
+
 #![feature(return_position_impl_trait_in_trait)]
 #![allow(incomplete_features)]
 
diff --git a/tests/ui/impl-trait/in-trait/object-safety.stderr b/tests/ui/impl-trait/in-trait/object-safety.current.stderr
index ca0e760ff6d..b7f2b019a77 100644
--- a/tests/ui/impl-trait/in-trait/object-safety.stderr
+++ b/tests/ui/impl-trait/in-trait/object-safety.current.stderr
@@ -1,11 +1,11 @@
 error[E0038]: the trait `Foo` cannot be made into an object
-  --> $DIR/object-safety.rs:17:33
+  --> $DIR/object-safety.rs:20:33
    |
 LL |     let i = Box::new(42_u32) as Box<dyn Foo>;
    |                                 ^^^^^^^^^^^^ `Foo` cannot be made into an object
    |
 note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
-  --> $DIR/object-safety.rs:7:22
+  --> $DIR/object-safety.rs:10:22
    |
 LL | trait Foo {
    |       --- this trait cannot be made into an object...
@@ -14,13 +14,13 @@ LL |     fn baz(&self) -> impl Debug;
    = help: consider moving `baz` to another trait
 
 error[E0038]: the trait `Foo` cannot be made into an object
-  --> $DIR/object-safety.rs:20:13
+  --> $DIR/object-safety.rs:23:13
    |
 LL |     let s = i.baz();
    |             ^^^^^^^ `Foo` cannot be made into an object
    |
 note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
-  --> $DIR/object-safety.rs:7:22
+  --> $DIR/object-safety.rs:10:22
    |
 LL | trait Foo {
    |       --- this trait cannot be made into an object...
@@ -29,13 +29,13 @@ LL |     fn baz(&self) -> impl Debug;
    = help: consider moving `baz` to another trait
 
 error[E0038]: the trait `Foo` cannot be made into an object
-  --> $DIR/object-safety.rs:17:13
+  --> $DIR/object-safety.rs:20:13
    |
 LL |     let i = Box::new(42_u32) as Box<dyn Foo>;
    |             ^^^^^^^^^^^^^^^^ `Foo` cannot be made into an object
    |
 note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
-  --> $DIR/object-safety.rs:7:22
+  --> $DIR/object-safety.rs:10:22
    |
 LL | trait Foo {
    |       --- this trait cannot be made into an object...
diff --git a/tests/ui/impl-trait/in-trait/object-safety.next.stderr b/tests/ui/impl-trait/in-trait/object-safety.next.stderr
new file mode 100644
index 00000000000..b7f2b019a77
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/object-safety.next.stderr
@@ -0,0 +1,50 @@
+error[E0038]: the trait `Foo` cannot be made into an object
+  --> $DIR/object-safety.rs:20:33
+   |
+LL |     let i = Box::new(42_u32) as Box<dyn Foo>;
+   |                                 ^^^^^^^^^^^^ `Foo` cannot be made into an object
+   |
+note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
+  --> $DIR/object-safety.rs:10:22
+   |
+LL | trait Foo {
+   |       --- this trait cannot be made into an object...
+LL |     fn baz(&self) -> impl Debug;
+   |                      ^^^^^^^^^^ ...because method `baz` references an `impl Trait` type in its return type
+   = help: consider moving `baz` to another trait
+
+error[E0038]: the trait `Foo` cannot be made into an object
+  --> $DIR/object-safety.rs:23:13
+   |
+LL |     let s = i.baz();
+   |             ^^^^^^^ `Foo` cannot be made into an object
+   |
+note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
+  --> $DIR/object-safety.rs:10:22
+   |
+LL | trait Foo {
+   |       --- this trait cannot be made into an object...
+LL |     fn baz(&self) -> impl Debug;
+   |                      ^^^^^^^^^^ ...because method `baz` references an `impl Trait` type in its return type
+   = help: consider moving `baz` to another trait
+
+error[E0038]: the trait `Foo` cannot be made into an object
+  --> $DIR/object-safety.rs:20:13
+   |
+LL |     let i = Box::new(42_u32) as Box<dyn Foo>;
+   |             ^^^^^^^^^^^^^^^^ `Foo` cannot be made into an object
+   |
+note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
+  --> $DIR/object-safety.rs:10:22
+   |
+LL | trait Foo {
+   |       --- this trait cannot be made into an object...
+LL |     fn baz(&self) -> impl Debug;
+   |                      ^^^^^^^^^^ ...because method `baz` references an `impl Trait` type in its return type
+   = help: consider moving `baz` to another trait
+   = note: required for `Box<u32>` to implement `CoerceUnsized<Box<dyn Foo>>`
+   = note: required by cast to type `Box<dyn Foo>`
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0038`.
diff --git a/tests/ui/impl-trait/in-trait/object-safety.rs b/tests/ui/impl-trait/in-trait/object-safety.rs
index dd35b9a2d8a..016a0aaae4b 100644
--- a/tests/ui/impl-trait/in-trait/object-safety.rs
+++ b/tests/ui/impl-trait/in-trait/object-safety.rs
@@ -1,3 +1,6 @@
+// [next] compile-flags: -Zlower-impl-trait-in-trait-to-assoc-ty
+// revisions: current next
+
 #![feature(return_position_impl_trait_in_trait)]
 #![allow(incomplete_features)]