Rollup merge of #120293 - estebank:issue-102629, r=nnethercote

Deduplicate more sized errors on call exprs

Change the implicit `Sized` `Obligation` `Span` for call expressions to include the whole expression. This aids the existing deduplication machinery to reduce the number of errors caused by a single unsized expression.

compiler/rustc_hir_typeck/src/callee.rs

@@ -77,6 +77,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     callee_expr,
                     Expectation::NoExpectation,
                     arg_exprs,
+                    Some(call_expr),
                 ),
             _ => self.check_expr(callee_expr),
         };

compiler/rustc_hir_typeck/src/expr.rs

@@ -177,7 +177,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expr: &'tcx hir::Expr<'tcx>,
         expected: Expectation<'tcx>,
     ) -> Ty<'tcx> {
-        self.check_expr_with_expectation_and_args(expr, expected, &[])
+        self.check_expr_with_expectation_and_args(expr, expected, &[], None)
     }
 
     /// Same as `check_expr_with_expectation`, but allows us to pass in the arguments of a
@@ -187,6 +187,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expr: &'tcx hir::Expr<'tcx>,
         expected: Expectation<'tcx>,
         args: &'tcx [hir::Expr<'tcx>],
+        call: Option<&'tcx hir::Expr<'tcx>>,
     ) -> Ty<'tcx> {
         if self.tcx().sess.verbose_internals() {
             // make this code only run with -Zverbose-internals because it is probably slow
@@ -233,7 +234,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let ty = ensure_sufficient_stack(|| match &expr.kind {
             hir::ExprKind::Path(
                 qpath @ (hir::QPath::Resolved(..) | hir::QPath::TypeRelative(..)),
-            ) => self.check_expr_path(qpath, expr, args),
+            ) => self.check_expr_path(qpath, expr, args, call),
             _ => self.check_expr_kind(expr, expected),
         });
         let ty = self.resolve_vars_if_possible(ty);
@@ -300,7 +301,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             ExprKind::Path(QPath::LangItem(lang_item, _)) => {
                 self.check_lang_item_path(lang_item, expr)
             }
-            ExprKind::Path(ref qpath) => self.check_expr_path(qpath, expr, &[]),
+            ExprKind::Path(ref qpath) => self.check_expr_path(qpath, expr, &[], None),
             ExprKind::InlineAsm(asm) => {
                 // We defer some asm checks as we may not have resolved the input and output types yet (they may still be infer vars).
                 self.deferred_asm_checks.borrow_mut().push((asm, expr.hir_id));
@@ -514,6 +515,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         qpath: &'tcx hir::QPath<'tcx>,
         expr: &'tcx hir::Expr<'tcx>,
         args: &'tcx [hir::Expr<'tcx>],
+        call: Option<&'tcx hir::Expr<'tcx>>,
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
         let (res, opt_ty, segs) =
@@ -530,7 +532,17 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 let e = report_unexpected_variant_res(tcx, res, qpath, expr.span, E0533, "value");
                 Ty::new_error(tcx, e)
             }
-            _ => self.instantiate_value_path(segs, opt_ty, res, expr.span, expr.hir_id).0,
+            _ => {
+                self.instantiate_value_path(
+                    segs,
+                    opt_ty,
+                    res,
+                    call.map_or(expr.span, |e| e.span),
+                    expr.span,
+                    expr.hir_id,
+                )
+                .0
+            }
         };
 
         if let ty::FnDef(did, _) = *ty.kind() {
@@ -585,7 +597,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 infer::BoundRegionConversionTime::FnCall,
                 fn_sig.output(),
             );
-            self.require_type_is_sized_deferred(output, expr.span, traits::SizedReturnType);
+            self.require_type_is_sized_deferred(
+                output,
+                call.map_or(expr.span, |e| e.span),
+                traits::SizedCallReturnType,
+            );
         }
 
         // We always require that the type provided as the value for

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -1073,6 +1073,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         self_ty: Option<LoweredTy<'tcx>>,
         res: Res,
         span: Span,
+        path_span: Span,
         hir_id: hir::HirId,
     ) -> (Ty<'tcx>, Res) {
         let tcx = self.tcx;
@@ -1106,7 +1107,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 match container {
                     ty::TraitContainer => callee::check_legal_trait_for_method_call(
                         tcx,
-                        span,
+                        path_span,
                         None,
                         span,
                         container_id,

compiler/rustc_hir_typeck/src/pat.rs

@@ -923,7 +923,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Type-check the path.
         let (pat_ty, pat_res) =
-            self.instantiate_value_path(segments, opt_ty, res, pat.span, pat.hir_id);
+            self.instantiate_value_path(segments, opt_ty, res, pat.span, pat.span, pat.hir_id);
         if let Some(err) =
             self.demand_suptype_with_origin(&self.pattern_cause(ti, pat.span), expected, pat_ty)
         {
@@ -1078,7 +1078,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Type-check the path.
         let (pat_ty, res) =
-            self.instantiate_value_path(segments, opt_ty, res, pat.span, pat.hir_id);
+            self.instantiate_value_path(segments, opt_ty, res, pat.span, pat.span, pat.hir_id);
         if !pat_ty.is_fn() {
             let e = report_unexpected_res(res);
             return Ty::new_error(tcx, e);

compiler/rustc_middle/src/traits/mod.rs

@@ -292,6 +292,8 @@ pub enum ObligationCauseCode<'tcx> {
     SizedArgumentType(Option<hir::HirId>),
     /// Return type must be `Sized`.
     SizedReturnType,
+    /// Return type of a call expression must be `Sized`.
+    SizedCallReturnType,
     /// Yield type must be `Sized`.
     SizedYieldType,
     /// Inline asm operand type must be `Sized`.

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -3292,7 +3292,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                     err.help("unsized fn params are gated as an unstable feature");
                 }
             }
-            ObligationCauseCode::SizedReturnType => {
+            ObligationCauseCode::SizedReturnType | ObligationCauseCode::SizedCallReturnType => {
                 err.note("the return type of a function must have a statically known size");
             }
             ObligationCauseCode::SizedYieldType => {

compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs

@@ -2493,7 +2493,15 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                     expr_finder.visit_expr(self.tcx.hir().body(body_id).value);
 
                     if let Some(hir::Expr {
-                        kind: hir::ExprKind::Path(hir::QPath::Resolved(None, path)),
+                        kind:
+                            hir::ExprKind::Call(
+                                hir::Expr {
+                                    kind: hir::ExprKind::Path(hir::QPath::Resolved(None, path)),
+                                    ..
+                                },
+                                _,
+                            )
+                            | hir::ExprKind::Path(hir::QPath::Resolved(None, path)),
                         ..
                     }) = expr_finder.result
                         && let [

tests/ui/anonymous-higher-ranked-lifetime.stderr

@@ -2,8 +2,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:2:5
    |
 LL |     f1(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'a, 'b> fn(&'a (), &'b ()) -> _`
@@ -22,8 +23,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:3:5
    |
 LL |     f2(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'a, 'b> fn(&'a (), &'b ()) -> _`
@@ -42,8 +44,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:4:5
    |
 LL |     f3(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'a> fn(&(), &'a ()) -> _`
@@ -62,8 +65,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:5:5
    |
 LL |     f4(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'r, 'a> fn(&'a (), &'r ()) -> _`
@@ -82,8 +86,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:6:5
    |
 LL |     f5(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'r> fn(&'r (), &'r ()) -> _`
@@ -102,8 +107,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:7:5
    |
 LL |     g1(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'a> fn(&'a (), Box<(dyn for<'a> Fn(&'a ()) + 'static)>) -> _`
@@ -122,8 +128,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:8:5
    |
 LL |     g2(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'a> fn(&'a (), for<'a> fn(&'a ())) -> _`
@@ -142,8 +149,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:9:5
    |
 LL |     g3(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'s> fn(&'s (), Box<(dyn for<'a> Fn(&'a ()) + 'static)>) -> _`
@@ -162,8 +170,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:10:5
    |
 LL |     g4(|_: (), _: ()| {});
-   |     ^^ -------------- found signature defined here
-   |     |
+   |     ^^^--------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'a> fn(&'a (), for<'r> fn(&'r ())) -> _`
@@ -182,8 +191,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:11:5
    |
 LL |     h1(|_: (), _: (), _: (), _: ()| {});
-   |     ^^ ---------------------------- found signature defined here
-   |     |
+   |     ^^^----------------------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'a, 'b> fn(&'a (), Box<(dyn for<'a> Fn(&'a ()) + 'static)>, &'b (), for<'a, 'b> fn(&'a (), &'b ())) -> _`
@@ -202,8 +212,9 @@ error[E0631]: type mismatch in closure arguments
   --> $DIR/anonymous-higher-ranked-lifetime.rs:12:5
    |
 LL |     h2(|_: (), _: (), _: (), _: ()| {});
-   |     ^^ ---------------------------- found signature defined here
-   |     |
+   |     ^^^----------------------------^^^^
+   |     |  |
+   |     |  found signature defined here
    |     expected due to this
    |
    = note: expected closure signature `for<'t0, 'a> fn(&'a (), Box<(dyn for<'a> Fn(&'a ()) + 'static)>, &'t0 (), for<'a, 'b> fn(&'a (), &'b ())) -> _`

tests/ui/associated-types/associated-types-path-2.rs

@@ -29,14 +29,12 @@ pub fn f1_uint_uint() {
     f1(2u32, 4u32);
     //~^ ERROR `u32: Foo` is not satisfied
     //~| ERROR `u32: Foo` is not satisfied
-    //~| ERROR `u32: Foo` is not satisfied
 }
 
 pub fn f1_uint_int() {
     f1(2u32, 4i32);
     //~^ ERROR `u32: Foo` is not satisfied
     //~| ERROR `u32: Foo` is not satisfied
-    //~| ERROR `u32: Foo` is not satisfied
 }
 
 pub fn f2_int() {

tests/ui/associated-types/associated-types-path-2.stderr

@@ -31,14 +31,6 @@ note: required by a bound in `f1`
 LL | pub fn f1<T: Foo>(a: T, x: T::A) {}
    |              ^^^ required by this bound in `f1`
 
-error[E0277]: the trait bound `u32: Foo` is not satisfied
-  --> $DIR/associated-types-path-2.rs:29:5
-   |
-LL |     f1(2u32, 4u32);
-   |     ^^^^^^^^^^^^^^ the trait `Foo` is not implemented for `u32`
-   |
-   = help: the trait `Foo` is implemented for `i32`
-
 error[E0277]: the trait bound `u32: Foo` is not satisfied
   --> $DIR/associated-types-path-2.rs:29:14
    |
@@ -48,7 +40,7 @@ LL |     f1(2u32, 4u32);
    = help: the trait `Foo` is implemented for `i32`
 
 error[E0277]: the trait bound `u32: Foo` is not satisfied
-  --> $DIR/associated-types-path-2.rs:36:8
+  --> $DIR/associated-types-path-2.rs:35:8
    |
 LL |     f1(2u32, 4i32);
    |     -- ^^^^ the trait `Foo` is not implemented for `u32`
@@ -63,23 +55,15 @@ LL | pub fn f1<T: Foo>(a: T, x: T::A) {}
    |              ^^^ required by this bound in `f1`
 
 error[E0277]: the trait bound `u32: Foo` is not satisfied
-  --> $DIR/associated-types-path-2.rs:36:5
-   |
-LL |     f1(2u32, 4i32);
-   |     ^^^^^^^^^^^^^^ the trait `Foo` is not implemented for `u32`
-   |
-   = help: the trait `Foo` is implemented for `i32`
-
-error[E0277]: the trait bound `u32: Foo` is not satisfied
-  --> $DIR/associated-types-path-2.rs:36:14
+  --> $DIR/associated-types-path-2.rs:35:14
    |
 LL |     f1(2u32, 4i32);
    |              ^^^^ the trait `Foo` is not implemented for `u32`
    |
    = help: the trait `Foo` is implemented for `i32`
 
 error[E0308]: mismatched types
-  --> $DIR/associated-types-path-2.rs:43:18
+  --> $DIR/associated-types-path-2.rs:41:18
    |
 LL |     let _: i32 = f2(2i32);
    |            ---   ^^^^^^^^ expected `i32`, found `u32`
@@ -91,7 +75,7 @@ help: you can convert a `u32` to an `i32` and panic if the converted value doesn
 LL |     let _: i32 = f2(2i32).try_into().unwrap();
    |                          ++++++++++++++++++++
 
-error: aborting due to 8 previous errors
+error: aborting due to 6 previous errors
 
 Some errors have detailed explanations: E0277, E0308.
 For more information about an error, try `rustc --explain E0277`.

tests/ui/associated-types/associated-types-unconstrained.stderr

@@ -5,7 +5,7 @@ LL |     fn bar() -> isize;
    |     ------------------ `Foo::bar` defined here
 ...
 LL |     let x: isize = Foo::bar();
-   |                    ^^^^^^^^ cannot call associated function of trait
+   |                    ^^^^^^^^^^ cannot call associated function of trait
    |
 help: use the fully-qualified path to the only available implementation
    |

tests/ui/async-await/async-is-unwindsafe.stderr

@@ -1,17 +1,19 @@
 error[E0277]: the type `&mut Context<'_>` may not be safely transferred across an unwind boundary
   --> $DIR/async-is-unwindsafe.rs:12:5
    |
-LL |       is_unwindsafe(async {
-   |  _____^^^^^^^^^^^^^_-
-   | |     |
-   | |     `&mut Context<'_>` may not be safely transferred across an unwind boundary
-LL | |
-LL | |         use std::ptr::null;
-LL | |         use std::task::{Context, RawWaker, RawWakerVTable, Waker};
-...  |
-LL | |         drop(cx_ref);
-LL | |     });
-   | |_____- within this `{async block@$DIR/async-is-unwindsafe.rs:12:19: 29:6}`
+LL |        is_unwindsafe(async {
+   |   _____^_____________-
+   |  |_____|
+   | ||
+LL | ||
+LL | ||         use std::ptr::null;
+LL | ||         use std::task::{Context, RawWaker, RawWakerVTable, Waker};
+...  ||
+LL | ||         drop(cx_ref);
+LL | ||     });
+   | ||_____-^ `&mut Context<'_>` may not be safely transferred across an unwind boundary
+   |  |_____|
+   |        within this `{async block@$DIR/async-is-unwindsafe.rs:12:19: 29:6}`
    |
    = help: within `{async block@$DIR/async-is-unwindsafe.rs:12:19: 29:6}`, the trait `UnwindSafe` is not implemented for `&mut Context<'_>`
    = note: `UnwindSafe` is implemented for `&Context<'_>`, but not for `&mut Context<'_>`