Auto merge of #117294 - matthiaskrgr:rollup-xylsec7, r=matthiaskrgr

Rollup of 7 pull requests

Successful merges:

 - #116834 (Remove `rustc_symbol_mangling/messages.ftl`.)
 - #117212 (Properly restore snapshot when failing to recover parsing ternary)
 - #117246 (Fix ICE: Restrict param constraint suggestion)
 - #117247 (NVPTX: Allow PassMode::Direct for ptx kernels for now)
 - #117270 (Hide internal methods from documentation)
 - #117281 (std::thread : add SAFETY comment)
 - #117287 (fix miri target information for Test step)

r? `@ghost`
`@rustbot` modify labels: rollup

Cargo.lock

@@ -4557,9 +4557,7 @@ dependencies = [
  "rustc-demangle",
  "rustc_data_structures",
  "rustc_errors",
- "rustc_fluent_macro",
  "rustc_hir",
- "rustc_macros",
  "rustc_middle",
  "rustc_session",
  "rustc_span",

compiler/rustc_codegen_llvm/src/abi.rs

@@ -362,9 +362,14 @@ impl<'ll, 'tcx> FnAbiLlvmExt<'ll, 'tcx> for FnAbi<'tcx, Ty<'tcx>> {
                         // currently use this mode so we have to allow it -- but we absolutely
                         // shouldn't let any more targets do that.
                         // (Also see <https://github.com/rust-lang/rust/issues/115666>.)
+                        //
+                        // The unstable abi `PtxKernel` also uses Direct for now.
+                        // It needs to switch to something else before stabilization can happen.
+                        // (See issue: https://github.com/rust-lang/rust/issues/117271)
                         assert!(
-                            matches!(&*cx.tcx.sess.target.arch, "wasm32" | "wasm64"),
-                            "`PassMode::Direct` for aggregates only allowed on wasm targets\nProblematic type: {:#?}",
+                            matches!(&*cx.tcx.sess.target.arch, "wasm32" | "wasm64")
+                                || self.conv == Conv::PtxKernel,
+                            "`PassMode::Direct` for aggregates only allowed on wasm and `extern \"ptx-kernel\"` fns\nProblematic type: {:#?}",
                             arg.layout,
                         );
                     }

compiler/rustc_driver_impl/src/lib.rs

@@ -136,7 +136,6 @@ pub static DEFAULT_LOCALE_RESOURCES: &[&str] = &[
     rustc_query_system::DEFAULT_LOCALE_RESOURCE,
     rustc_resolve::DEFAULT_LOCALE_RESOURCE,
     rustc_session::DEFAULT_LOCALE_RESOURCE,
-    rustc_symbol_mangling::DEFAULT_LOCALE_RESOURCE,
     rustc_trait_selection::DEFAULT_LOCALE_RESOURCE,
     rustc_ty_utils::DEFAULT_LOCALE_RESOURCE,
     // tidy-alphabetical-end

compiler/rustc_infer/src/infer/error_reporting/note_and_explain.rs

@@ -54,13 +54,17 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                     }
                     (ty::Param(expected), ty::Param(found)) => {
                         let generics = tcx.generics_of(body_owner_def_id);
-                        let e_span = tcx.def_span(generics.type_param(expected, tcx).def_id);
-                        if !sp.contains(e_span) {
-                            diag.span_label(e_span, "expected type parameter");
+                        if let Some(param) = generics.opt_type_param(expected, tcx) {
+                            let e_span = tcx.def_span(param.def_id);
+                            if !sp.contains(e_span) {
+                                diag.span_label(e_span, "expected type parameter");
+                            }
                         }
-                        let f_span = tcx.def_span(generics.type_param(found, tcx).def_id);
-                        if !sp.contains(f_span) {
-                            diag.span_label(f_span, "found type parameter");
+                        if let Some(param) = generics.opt_type_param(found, tcx) {
+                            let f_span = tcx.def_span(param.def_id);
+                            if !sp.contains(f_span) {
+                                diag.span_label(f_span, "found type parameter");
+                            }
                         }
                         diag.note(
                             "a type parameter was expected, but a different one was found; \
@@ -83,23 +87,29 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                     | (ty::Alias(ty::Projection, proj), ty::Param(p))
                         if !tcx.is_impl_trait_in_trait(proj.def_id) =>
                     {
-                        let p_def_id = tcx.generics_of(body_owner_def_id).type_param(p, tcx).def_id;
-                        let p_span = tcx.def_span(p_def_id);
-                        let expected = match (values.expected.kind(), values.found.kind()) {
-                            (ty::Param(_), _) => "expected ",
-                            (_, ty::Param(_)) => "found ",
-                            _ => "",
-                        };
-                        if !sp.contains(p_span) {
-                            diag.span_label(p_span, format!("{expected}this type parameter"));
-                        }
-                        let hir = tcx.hir();
+                        let parent = tcx.generics_of(body_owner_def_id)
+                            .opt_type_param(p, tcx)
+                            .and_then(|param| {
+                                let p_def_id = param.def_id;
+                                let p_span = tcx.def_span(p_def_id);
+                                let expected = match (values.expected.kind(), values.found.kind()) {
+                                    (ty::Param(_), _) => "expected ",
+                                    (_, ty::Param(_)) => "found ",
+                                    _ => "",
+                                };
+                                if !sp.contains(p_span) {
+                                    diag.span_label(
+                                        p_span,
+                                        format!("{expected}this type parameter"),
+                                    );
+                                }
+                                p_def_id.as_local().and_then(|id| {
+                                    let local_id = tcx.hir().local_def_id_to_hir_id(id);
+                                    let generics = tcx.hir().find_parent(local_id)?.generics()?;
+                                    Some((id, generics))
+                                })
+                            });
                         let mut note = true;
-                        let parent = p_def_id.as_local().and_then(|id| {
-                            let local_id = hir.local_def_id_to_hir_id(id);
-                            let generics = tcx.hir().find_parent(local_id)?.generics()?;
-                            Some((id, generics))
-                        });
                         if let Some((local_id, generics)) = parent {
                             // Synthesize the associated type restriction `Add<Output = Expected>`.
                             // FIXME: extract this logic for use in other diagnostics.
@@ -172,14 +182,16 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                     (ty::Param(p), ty::Dynamic(..) | ty::Alias(ty::Opaque, ..))
                     | (ty::Dynamic(..) | ty::Alias(ty::Opaque, ..), ty::Param(p)) => {
                         let generics = tcx.generics_of(body_owner_def_id);
-                        let p_span = tcx.def_span(generics.type_param(p, tcx).def_id);
-                        let expected = match (values.expected.kind(), values.found.kind()) {
-                            (ty::Param(_), _) => "expected ",
-                            (_, ty::Param(_)) => "found ",
-                            _ => "",
-                        };
-                        if !sp.contains(p_span) {
-                            diag.span_label(p_span, format!("{expected}this type parameter"));
+                        if let Some(param) = generics.opt_type_param(p, tcx) {
+                            let p_span = tcx.def_span(param.def_id);
+                            let expected = match (values.expected.kind(), values.found.kind()) {
+                                (ty::Param(_), _) => "expected ",
+                                (_, ty::Param(_)) => "found ",
+                                _ => "",
+                            };
+                            if !sp.contains(p_span) {
+                                diag.span_label(p_span, format!("{expected}this type parameter"));
+                            }
                         }
                         diag.help("type parameters must be constrained to match other types");
                         if tcx.sess.teach(&diag.get_code().unwrap()) {
@@ -217,9 +229,11 @@ impl<T> Trait<T> for X {
                     }
                     (ty::Param(p), ty::Closure(..) | ty::Coroutine(..)) => {
                         let generics = tcx.generics_of(body_owner_def_id);
-                        let p_span = tcx.def_span(generics.type_param(p, tcx).def_id);
-                        if !sp.contains(p_span) {
-                            diag.span_label(p_span, "expected this type parameter");
+                        if let Some(param) = generics.opt_type_param(p, tcx) {
+                            let p_span = tcx.def_span(param.def_id);
+                            if !sp.contains(p_span) {
+                                diag.span_label(p_span, "expected this type parameter");
+                            }
                         }
                         diag.help(format!(
                             "every closure has a distinct type and so could not always match the \
@@ -228,14 +242,16 @@ impl<T> Trait<T> for X {
                     }
                     (ty::Param(p), _) | (_, ty::Param(p)) => {
                         let generics = tcx.generics_of(body_owner_def_id);
-                        let p_span = tcx.def_span(generics.type_param(p, tcx).def_id);
-                        let expected = match (values.expected.kind(), values.found.kind()) {
-                            (ty::Param(_), _) => "expected ",
-                            (_, ty::Param(_)) => "found ",
-                            _ => "",
-                        };
-                        if !sp.contains(p_span) {
-                            diag.span_label(p_span, format!("{expected}this type parameter"));
+                        if let Some(param) = generics.opt_type_param(p, tcx) {
+                            let p_span = tcx.def_span(param.def_id);
+                            let expected = match (values.expected.kind(), values.found.kind()) {
+                                (ty::Param(_), _) => "expected ",
+                                (_, ty::Param(_)) => "found ",
+                                _ => "",
+                            };
+                            if !sp.contains(p_span) {
+                                diag.span_label(p_span, format!("{expected}this type parameter"));
+                            }
                         }
                     }
                     (ty::Alias(ty::Projection | ty::Inherent, proj_ty), _)
@@ -364,13 +380,14 @@ impl<T> Trait<T> for X {
         };
         // Get the `DefId` for the type parameter corresponding to `A` in `<A as T>::Foo`.
         // This will also work for `impl Trait`.
-        let def_id = if let ty::Param(param_ty) = proj_ty.self_ty().kind() {
-            let generics = tcx.generics_of(body_owner_def_id);
-            generics.type_param(param_ty, tcx).def_id
-        } else {
+        let ty::Param(param_ty) = proj_ty.self_ty().kind() else {
             return false;
         };
-        let Some(def_id) = def_id.as_local() else {
+        let generics = tcx.generics_of(body_owner_def_id);
+        let Some(param) = generics.opt_type_param(param_ty, tcx) else {
+            return false;
+        };
+        let Some(def_id) = param.def_id.as_local() else {
             return false;
         };
 
@@ -390,6 +407,10 @@ impl<T> Trait<T> for X {
                 return true;
             }
         }
+        if (param_ty.index as usize) >= generics.parent_count {
+            // The param comes from the current item, do not look at the parent. (#117209)
+            return false;
+        }
         // If associated item, look to constrain the params of the trait/impl.
         let hir_id = match item {
             hir::Node::ImplItem(item) => item.hir_id(),

compiler/rustc_middle/src/ty/generics.rs

@@ -237,6 +237,20 @@ impl<'tcx> Generics {
         }
     }
 
+    /// Returns the `GenericParamDef` with the given index if available.
+    pub fn opt_param_at(
+        &'tcx self,
+        param_index: usize,
+        tcx: TyCtxt<'tcx>,
+    ) -> Option<&'tcx GenericParamDef> {
+        if let Some(index) = param_index.checked_sub(self.parent_count) {
+            self.params.get(index)
+        } else {
+            tcx.generics_of(self.parent.expect("parent_count > 0 but no parent?"))
+                .opt_param_at(param_index, tcx)
+        }
+    }
+
     pub fn params_to(&'tcx self, param_index: usize, tcx: TyCtxt<'tcx>) -> &'tcx [GenericParamDef] {
         if let Some(index) = param_index.checked_sub(self.parent_count) {
             &self.params[..index]
@@ -268,6 +282,20 @@ impl<'tcx> Generics {
         }
     }
 
+    /// Returns the `GenericParamDef` associated with this `ParamTy` if it belongs to this
+    /// `Generics`.
+    pub fn opt_type_param(
+        &'tcx self,
+        param: &ParamTy,
+        tcx: TyCtxt<'tcx>,
+    ) -> Option<&'tcx GenericParamDef> {
+        let param = self.opt_param_at(param.index as usize, tcx)?;
+        match param.kind {
+            GenericParamDefKind::Type { .. } => Some(param),
+            _ => None,
+        }
+    }
+
     /// Returns the `GenericParamDef` associated with this `ParamConst`.
     pub fn const_param(&'tcx self, param: &ParamConst, tcx: TyCtxt<'tcx>) -> &GenericParamDef {
         let param = self.param_at(param.index as usize, tcx);

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -504,8 +504,10 @@ impl<'a> Parser<'a> {
 
         // Special-case "expected `;`" errors
         if expected.contains(&TokenType::Token(token::Semi)) {
-            if self.prev_token == token::Question && self.maybe_recover_from_ternary_operator() {
-                return Ok(true);
+            // If the user is trying to write a ternary expression, recover it and
+            // return an Err to prevent a cascade of irrelevant diagnostics
+            if self.prev_token == token::Question && let Err(e) = self.maybe_recover_from_ternary_operator() {
+                return Err(e);
             }
 
             if self.token.span == DUMMY_SP || self.prev_token.span == DUMMY_SP {
@@ -1428,10 +1430,10 @@ impl<'a> Parser<'a> {
 
     /// Rust has no ternary operator (`cond ? then : else`). Parse it and try
     /// to recover from it if `then` and `else` are valid expressions. Returns
-    /// whether it was a ternary operator.
-    pub(super) fn maybe_recover_from_ternary_operator(&mut self) -> bool {
+    /// an err if this appears to be a ternary expression.
+    pub(super) fn maybe_recover_from_ternary_operator(&mut self) -> PResult<'a, ()> {
         if self.prev_token != token::Question {
-            return false;
+            return PResult::Ok(());
         }
 
         let lo = self.prev_token.span.lo();
@@ -1449,20 +1451,18 @@ impl<'a> Parser<'a> {
             if self.eat_noexpect(&token::Colon) {
                 match self.parse_expr() {
                     Ok(_) => {
-                        self.sess.emit_err(TernaryOperator { span: self.token.span.with_lo(lo) });
-                        return true;
+                        return Err(self
+                            .sess
+                            .create_err(TernaryOperator { span: self.token.span.with_lo(lo) }));
                     }
                     Err(err) => {
                         err.cancel();
-                        self.restore_snapshot(snapshot);
                     }
                 };
             }
-        } else {
-            self.restore_snapshot(snapshot);
-        };
-
-        false
+        }
+        self.restore_snapshot(snapshot);
+        Ok(())
     }
 
     pub(super) fn maybe_recover_from_bad_type_plus(&mut self, ty: &Ty) -> PResult<'a, ()> {

compiler/rustc_symbol_mangling/Cargo.toml

@@ -15,9 +15,7 @@ twox-hash = "1.6.3"
 rustc_span = { path = "../rustc_span" }
 rustc_middle = { path = "../rustc_middle" }
 rustc_hir = { path = "../rustc_hir" }
-rustc_fluent_macro = { path = "../rustc_fluent_macro" }
 rustc_target = { path = "../rustc_target" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_session = { path = "../rustc_session" }
-rustc_macros = { path = "../rustc_macros" }
 rustc_errors = { path = "../rustc_errors" }

compiler/rustc_symbol_mangling/messages.ftl

@@ -1 +0,0 @@
-symbol_mangling_test_output = {$kind}({$content})

compiler/rustc_symbol_mangling/src/errors.rs

@@ -1,18 +1,32 @@
 //! Errors emitted by symbol_mangling.
 
-use rustc_errors::{DiagnosticArgValue, IntoDiagnosticArg};
-use rustc_macros::Diagnostic;
+use rustc_errors::{ErrorGuaranteed, IntoDiagnostic};
 use rustc_span::Span;
+use std::fmt;
 
-#[derive(Diagnostic)]
-#[diag(symbol_mangling_test_output)]
 pub struct TestOutput {
-    #[primary_span]
     pub span: Span,
     pub kind: Kind,
     pub content: String,
 }
 
+// This diagnostic doesn't need translation because (a) it doesn't contain any
+// natural language, and (b) it's only used in tests. So we construct it
+// manually and avoid the fluent machinery.
+impl IntoDiagnostic<'_> for TestOutput {
+    fn into_diagnostic(
+        self,
+        handler: &'_ rustc_errors::Handler,
+    ) -> rustc_errors::DiagnosticBuilder<'_, ErrorGuaranteed> {
+        let TestOutput { span, kind, content } = self;
+
+        #[allow(rustc::untranslatable_diagnostic)]
+        let mut diag = handler.struct_err(format!("{kind}({content})"));
+        diag.set_span(span);
+        diag
+    }
+}
+
 pub enum Kind {
     SymbolName,
     Demangling,
@@ -20,15 +34,13 @@ pub enum Kind {
     DefPath,
 }
 
-impl IntoDiagnosticArg for Kind {
-    fn into_diagnostic_arg(self) -> DiagnosticArgValue<'static> {
-        let kind = match self {
-            Kind::SymbolName => "symbol-name",
-            Kind::Demangling => "demangling",
-            Kind::DemanglingAlt => "demangling-alt",
-            Kind::DefPath => "def-path",
+impl fmt::Display for Kind {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Kind::SymbolName => write!(f, "symbol-name"),
+            Kind::Demangling => write!(f, "demangling"),
+            Kind::DemanglingAlt => write!(f, "demangling-alt"),
+            Kind::DefPath => write!(f, "def-path"),
         }
-        .into();
-        DiagnosticArgValue::Str(kind)
     }
 }

compiler/rustc_symbol_mangling/src/lib.rs

@@ -103,8 +103,6 @@ extern crate rustc_middle;
 #[macro_use]
 extern crate tracing;
 
-use rustc_errors::{DiagnosticMessage, SubdiagnosticMessage};
-use rustc_fluent_macro::fluent_messages;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
@@ -121,8 +119,6 @@ pub mod errors;
 pub mod test;
 pub mod typeid;
 
-fluent_messages! { "../messages.ftl" }
-
 /// This function computes the symbol name for the given `instance` and the
 /// given instantiating crate. That is, if you know that instance X is
 /// instantiated in crate Y, this is the symbol name this instance would have.

library/std/src/io/mod.rs

@@ -317,6 +317,7 @@ pub use self::stdio::set_output_capture;
 #[stable(feature = "is_terminal", since = "1.70.0")]
 pub use self::stdio::IsTerminal;
 #[unstable(feature = "print_internals", issue = "none")]
+#[doc(hidden)]
 pub use self::stdio::{_eprint, _print};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use self::{

library/std/src/thread/mod.rs

@@ -546,6 +546,8 @@ impl Builder {
         }
 
         let main = Box::new(main);
+        // SAFETY: dynamic size and alignment of the Box remain the same. See below for why the
+        // lifetime change is justified.
         #[cfg(bootstrap)]
         let main =
             unsafe { mem::transmute::<Box<dyn FnOnce() + 'a>, Box<dyn FnOnce() + 'static>>(main) };

src/bootstrap/src/core/build_steps/test.rs

@@ -630,7 +630,7 @@ impl Step for Miri {
             SourceType::InTree,
             &[],
         );
-        let _guard = builder.msg_sysroot_tool(Kind::Test, compiler.stage, "miri", host, host);
+        let _guard = builder.msg_sysroot_tool(Kind::Test, compiler.stage, "miri", host, target);
 
         cargo.add_rustc_lib_path(builder, compiler);
 

tests/ui/associated-type-bounds/do-not-look-at-parent-item-in-suggestion-for-type-param-of-current-assoc-item.rs

@@ -0,0 +1,28 @@
+use std::collections::HashMap;
+use std::hash::Hash;
+
+trait LowT: Identify {}
+
+trait Identify {
+    type Id: Clone + Hash + PartialEq + Eq;
+    fn identify(&self) -> Self::Id;
+}
+
+struct MapStore<L, I>
+where
+    L: LowT + Identify<Id = I>,
+{
+    lows: HashMap<I, L>,
+}
+
+impl<L, I> MapStore<L, I>
+where
+    L: LowT + Identify<Id = I>,
+    I: Clone + Hash + PartialEq + Eq,
+{
+    fn remove_low(&mut self, low: &impl LowT) {
+        let _low = self.lows.remove(low.identify()).unwrap(); //~ ERROR mismatched types
+    }
+}
+
+fn main() {}

tests/ui/associated-type-bounds/do-not-look-at-parent-item-in-suggestion-for-type-param-of-current-assoc-item.stderr

@@ -0,0 +1,18 @@
+error[E0308]: mismatched types
+  --> $DIR/do-not-look-at-parent-item-in-suggestion-for-type-param-of-current-assoc-item.rs:24:37
+   |
+LL |         let _low = self.lows.remove(low.identify()).unwrap();
+   |                              ------ ^^^^^^^^^^^^^^ expected `&I`, found associated type
+   |                              |
+   |                              arguments to this method are incorrect
+   |
+   = note:    expected reference `&I`
+           found associated type `<impl LowT as Identify>::Id`
+   = help: consider constraining the associated type `<impl LowT as Identify>::Id` to `&I`
+   = note: for more information, visit https://doc.rust-lang.org/book/ch19-03-advanced-traits.html
+note: method defined here
+  --> $SRC_DIR/std/src/collections/hash/map.rs:LL:COL
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.

tests/ui/malformed/do-not-ice-on-note_and_explain.rs

@@ -0,0 +1,7 @@
+struct A<B>(B);
+impl<B>A<B>{fn d(){fn d(){Self(1)}}}
+//~^ ERROR the size for values of type `B` cannot be known at compilation time
+//~| ERROR the size for values of type `B` cannot be known at compilation time
+//~| ERROR mismatched types
+//~| ERROR mismatched types
+//~| ERROR `main` function not found in crate

tests/ui/malformed/do-not-ice-on-note_and_explain.stderr

@@ -0,0 +1,79 @@
+error[E0601]: `main` function not found in crate `do_not_ice_on_note_and_explain`
+  --> $DIR/do-not-ice-on-note_and_explain.rs:2:37
+   |
+LL | impl<B>A<B>{fn d(){fn d(){Self(1)}}}
+   |                                     ^ consider adding a `main` function to `$DIR/do-not-ice-on-note_and_explain.rs`
+
+error[E0277]: the size for values of type `B` cannot be known at compilation time
+  --> $DIR/do-not-ice-on-note_and_explain.rs:2:32
+   |
+LL | impl<B>A<B>{fn d(){fn d(){Self(1)}}}
+   |      -                    ---- ^ doesn't have a size known at compile-time
+   |      |                    |
+   |      |                    required by a bound introduced by this call
+   |      this type parameter needs to be `Sized`
+   |
+note: required by a bound in `A`
+  --> $DIR/do-not-ice-on-note_and_explain.rs:1:10
+   |
+LL | struct A<B>(B);
+   |          ^ required by this bound in `A`
+
+error[E0308]: mismatched types
+  --> $DIR/do-not-ice-on-note_and_explain.rs:2:32
+   |
+LL | impl<B>A<B>{fn d(){fn d(){Self(1)}}}
+   |                           ---- ^ expected type parameter `B`, found integer
+   |                           |
+   |                           arguments to this function are incorrect
+   |
+   = note: expected type parameter `B`
+                        found type `{integer}`
+note: tuple struct defined here
+  --> $DIR/do-not-ice-on-note_and_explain.rs:1:8
+   |
+LL | struct A<B>(B);
+   |        ^
+
+error[E0308]: mismatched types
+  --> $DIR/do-not-ice-on-note_and_explain.rs:2:27
+   |
+LL | impl<B>A<B>{fn d(){fn d(){Self(1)}}}
+   |                           ^^^^^^^ expected `()`, found `A<B>`
+   |
+   = note: expected unit type `()`
+                 found struct `A<B>`
+help: consider using a semicolon here
+   |
+LL | impl<B>A<B>{fn d(){fn d(){Self(1);}}}
+   |                                  +
+help: try adding a return type
+   |
+LL | impl<B>A<B>{fn d(){fn d() -> A<B>{Self(1)}}}
+   |                           +++++++
+
+error[E0277]: the size for values of type `B` cannot be known at compilation time
+  --> $DIR/do-not-ice-on-note_and_explain.rs:2:27
+   |
+LL | impl<B>A<B>{fn d(){fn d(){Self(1)}}}
+   |      -                    ^^^^^^^ doesn't have a size known at compile-time
+   |      |
+   |      this type parameter needs to be `Sized`
+   |
+note: required by a bound in `A`
+  --> $DIR/do-not-ice-on-note_and_explain.rs:1:10
+   |
+LL | struct A<B>(B);
+   |          ^ required by this bound in `A`
+help: you could relax the implicit `Sized` bound on `B` if it were used through indirection like `&B` or `Box<B>`
+  --> $DIR/do-not-ice-on-note_and_explain.rs:1:10
+   |
+LL | struct A<B>(B);
+   |          ^  - ...if indirection were used here: `Box<B>`
+   |          |
+   |          this could be changed to `B: ?Sized`...
+
+error: aborting due to 5 previous errors
+
+Some errors have detailed explanations: E0277, E0308, E0601.
+For more information about an error, try `rustc --explain E0277`.

tests/ui/parser/ternary_operator.rs

@@ -1,69 +1,30 @@
-// A good chunk of these errors aren't shown to the user, but are still
-// required in the test for it to pass.
-
-fn a() { //~ NOTE this function should return `Result` or `Option` to accept `?`
+fn a() {
     let x = 5 > 2 ? true : false;
     //~^ ERROR Rust has no ternary operator
     //~| HELP use an `if-else` expression instead
-    //~| ERROR the `?` operator can only be applied to values that implement `Try` [E0277]
-    //~| HELP the trait `Try` is not implemented for `{integer}`
-    //~| ERROR the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`) [E0277]
-    //~| HELP the trait `FromResidual<_>` is not implemented for `()`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE the `?` operator cannot be applied to type `{integer}`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE cannot use the `?` operator in a function that returns `()`
-    //~| NOTE in this expansion of desugaring of operator `?`
 }
 
-fn b() { //~ NOTE this function should return `Result` or `Option` to accept `?`
+fn b() {
     let x = 5 > 2 ? { true } : { false };
     //~^ ERROR Rust has no ternary operator
     //~| HELP use an `if-else` expression instead
-    //~| ERROR the `?` operator can only be applied to values that implement `Try` [E0277]
-    //~| HELP the trait `Try` is not implemented for `{integer}`
-    //~| ERROR the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`) [E0277]
-    //~| HELP the trait `FromResidual<_>` is not implemented for `()`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE the `?` operator cannot be applied to type `{integer}`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE cannot use the `?` operator in a function that returns `()`
-    //~| NOTE in this expansion of desugaring of operator `?`
 }
 
-fn c() { //~ NOTE this function should return `Result` or `Option` to accept `?`
+fn c() {
     let x = 5 > 2 ? f32::MAX : f32::MIN;
     //~^ ERROR Rust has no ternary operator
     //~| HELP use an `if-else` expression instead
-    //~| ERROR the `?` operator can only be applied to values that implement `Try` [E0277]
-    //~| HELP the trait `Try` is not implemented for `{integer}`
-    //~| ERROR the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`) [E0277]
-    //~| HELP the trait `FromResidual<_>` is not implemented for `()`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE the `?` operator cannot be applied to type `{integer}`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE cannot use the `?` operator in a function that returns `()`
-    //~| NOTE in this expansion of desugaring of operator `?`
 }
 
-fn main() { //~ NOTE this function should return `Result` or `Option` to accept `?`
+fn bad() {
+    // regression test for #117208
+    v ? return;
+    //~^ ERROR expected one of
+}
+
+fn main() {
     let x = 5 > 2 ? { let x = vec![]: Vec<u16>; x } : { false };
     //~^ ERROR Rust has no ternary operator
     //~| HELP use an `if-else` expression instead
     //~| ERROR expected one of `.`, `;`, `?`, `else`, or an operator, found `:`
-    //~| NOTE expected one of `.`, `;`, `?`, `else`, or an operator
-    //~| ERROR the `?` operator can only be applied to values that implement `Try` [E0277]
-    //~| HELP the trait `Try` is not implemented for `{integer}`
-    //~| ERROR the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`) [E0277]
-    //~| HELP the trait `FromResidual<_>` is not implemented for `()`
-    //~| NOTE type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE the `?` operator cannot be applied to type `{integer}`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE in this expansion of desugaring of operator `?`
-    //~| NOTE cannot use the `?` operator in a function that returns `()`
-    //~| NOTE in this expansion of desugaring of operator `?`
 }

tests/ui/parser/ternary_operator.stderr

@@ -1,5 +1,5 @@
 error: Rust has no ternary operator
-  --> $DIR/ternary_operator.rs:5:19
+  --> $DIR/ternary_operator.rs:2:19
    |
 LL |     let x = 5 > 2 ? true : false;
    |                   ^^^^^^^^^^^^^^^
@@ -7,7 +7,7 @@ LL |     let x = 5 > 2 ? true : false;
    = help: use an `if-else` expression instead
 
 error: Rust has no ternary operator
-  --> $DIR/ternary_operator.rs:21:19
+  --> $DIR/ternary_operator.rs:8:19
    |
 LL |     let x = 5 > 2 ? { true } : { false };
    |                   ^^^^^^^^^^^^^^^^^^^^^^^
@@ -15,15 +15,21 @@ LL |     let x = 5 > 2 ? { true } : { false };
    = help: use an `if-else` expression instead
 
 error: Rust has no ternary operator
-  --> $DIR/ternary_operator.rs:37:19
+  --> $DIR/ternary_operator.rs:14:19
    |
 LL |     let x = 5 > 2 ? f32::MAX : f32::MIN;
    |                   ^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: use an `if-else` expression instead
 
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found keyword `return`
+  --> $DIR/ternary_operator.rs:21:9
+   |
+LL |     v ? return;
+   |         ^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
+
 error: expected one of `.`, `;`, `?`, `else`, or an operator, found `:`
-  --> $DIR/ternary_operator.rs:53:37
+  --> $DIR/ternary_operator.rs:26:37
    |
 LL |     let x = 5 > 2 ? { let x = vec![]: Vec<u16>; x } : { false };
    |                                     ^ expected one of `.`, `;`, `?`, `else`, or an operator
@@ -31,85 +37,12 @@ LL |     let x = 5 > 2 ? { let x = vec![]: Vec<u16>; x } : { false };
    = note: type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
 
 error: Rust has no ternary operator
-  --> $DIR/ternary_operator.rs:53:19
+  --> $DIR/ternary_operator.rs:26:19
    |
 LL |     let x = 5 > 2 ? { let x = vec![]: Vec<u16>; x } : { false };
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = help: use an `if-else` expression instead
 
-error[E0277]: the `?` operator can only be applied to values that implement `Try`
-  --> $DIR/ternary_operator.rs:5:17
-   |
-LL |     let x = 5 > 2 ? true : false;
-   |                 ^^^ the `?` operator cannot be applied to type `{integer}`
-   |
-   = help: the trait `Try` is not implemented for `{integer}`
+error: aborting due to 6 previous errors
 
-error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
-  --> $DIR/ternary_operator.rs:5:19
-   |
-LL | fn a() {
-   | ------ this function should return `Result` or `Option` to accept `?`
-LL |     let x = 5 > 2 ? true : false;
-   |                   ^ cannot use the `?` operator in a function that returns `()`
-   |
-   = help: the trait `FromResidual<_>` is not implemented for `()`
-
-error[E0277]: the `?` operator can only be applied to values that implement `Try`
-  --> $DIR/ternary_operator.rs:21:17
-   |
-LL |     let x = 5 > 2 ? { true } : { false };
-   |                 ^^^ the `?` operator cannot be applied to type `{integer}`
-   |
-   = help: the trait `Try` is not implemented for `{integer}`
-
-error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
-  --> $DIR/ternary_operator.rs:21:19
-   |
-LL | fn b() {
-   | ------ this function should return `Result` or `Option` to accept `?`
-LL |     let x = 5 > 2 ? { true } : { false };
-   |                   ^ cannot use the `?` operator in a function that returns `()`
-   |
-   = help: the trait `FromResidual<_>` is not implemented for `()`
-
-error[E0277]: the `?` operator can only be applied to values that implement `Try`
-  --> $DIR/ternary_operator.rs:37:17
-   |
-LL |     let x = 5 > 2 ? f32::MAX : f32::MIN;
-   |                 ^^^ the `?` operator cannot be applied to type `{integer}`
-   |
-   = help: the trait `Try` is not implemented for `{integer}`
-
-error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
-  --> $DIR/ternary_operator.rs:37:19
-   |
-LL | fn c() {
-   | ------ this function should return `Result` or `Option` to accept `?`
-LL |     let x = 5 > 2 ? f32::MAX : f32::MIN;
-   |                   ^ cannot use the `?` operator in a function that returns `()`
-   |
-   = help: the trait `FromResidual<_>` is not implemented for `()`
-
-error[E0277]: the `?` operator can only be applied to values that implement `Try`
-  --> $DIR/ternary_operator.rs:53:17
-   |
-LL |     let x = 5 > 2 ? { let x = vec![]: Vec<u16>; x } : { false };
-   |                 ^^^ the `?` operator cannot be applied to type `{integer}`
-   |
-   = help: the trait `Try` is not implemented for `{integer}`
-
-error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
-  --> $DIR/ternary_operator.rs:53:19
-   |
-LL | fn main() {
-   | --------- this function should return `Result` or `Option` to accept `?`
-LL |     let x = 5 > 2 ? { let x = vec![]: Vec<u16>; x } : { false };
-   |                   ^ cannot use the `?` operator in a function that returns `()`
-   |
-   = help: the trait `FromResidual<_>` is not implemented for `()`
-
-error: aborting due to 13 previous errors
-
-For more information about this error, try `rustc --explain E0277`.