Rollup of 4 pull requests

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -3536,17 +3536,18 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                 && let ty::Adt(adt_def, _) = return_ty.kind()
                 && adt_def.did() == cow_did
             {
-                if let Ok(snippet) = tcx.sess.source_map().span_to_snippet(return_span) {
-                    if let Some(pos) = snippet.rfind(".to_owned") {
-                        let byte_pos = BytePos(pos as u32 + 1u32);
-                        let to_owned_span = return_span.with_hi(return_span.lo() + byte_pos);
-                        err.span_suggestion_short(
-                            to_owned_span.shrink_to_hi(),
-                            "try using `.into_owned()` if you meant to convert a `Cow<'_, T>` to an owned `T`",
-                            "in",
-                            Applicability::MaybeIncorrect,
-                        );
-                    }
+                let typeck = tcx.typeck(self.mir_def_id());
+                if let Some(expr) = self.find_expr(return_span)
+                    && let Some(def_id) = typeck.type_dependent_def_id(expr.hir_id)
+                    && tcx.is_diagnostic_item(sym::to_owned_method, def_id)
+                    && let Some(to_owned_ident) = expr.method_ident()
+                {
+                    err.span_suggestion_short(
+                        to_owned_ident.span.shrink_to_lo(),
+                        "try using `.into_owned()` if you meant to convert a `Cow<'_, T>` to an owned `T`",
+                        "in",
+                        Applicability::MaybeIncorrect,
+                    );
                 }
             }
         }

compiler/rustc_borrowck/src/universal_regions.rs

@@ -23,6 +23,7 @@ use rustc_hir::lang_items::LangItem;
 use rustc_index::IndexVec;
 use rustc_infer::infer::NllRegionVariableOrigin;
 use rustc_macros::extension;
+use rustc_middle::mir::RETURN_PLACE;
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{
     self, GenericArgs, GenericArgsRef, InlineConstArgs, InlineConstArgsParts, RegionVid, Ty,
@@ -584,7 +585,6 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
     /// see `DefiningTy` for details.
     fn defining_ty(&self) -> DefiningTy<'tcx> {
         let tcx = self.infcx.tcx;
-        let typeck_root_def_id = tcx.typeck_root_def_id_local(self.mir_def);
 
         match tcx.hir_body_owner_kind(self.mir_def) {
             BodyOwnerKind::Closure | BodyOwnerKind::Fn => {
@@ -614,36 +614,40 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
             }
 
             BodyOwnerKind::Const { .. } | BodyOwnerKind::Static(..) => {
-                let identity_args = GenericArgs::identity_for_item(tcx, typeck_root_def_id);
-                if self.mir_def == typeck_root_def_id {
-                    let args = self.infcx.replace_free_regions_with_nll_infer_vars(
-                        NllRegionVariableOrigin::FreeRegion,
-                        identity_args,
-                    );
-                    DefiningTy::Const(self.mir_def.to_def_id(), args)
-                } else {
-                    // FIXME: this line creates a query dependency between borrowck and typeck.
-                    //
-                    // This is required for `AscribeUserType` canonical query, which will call
-                    // `type_of(inline_const_def_id)`. That `type_of` would inject erased lifetimes
-                    // into borrowck, which is ICE #78174.
-                    //
-                    // As a workaround, inline consts have an additional generic param (`ty`
-                    // below), so that `type_of(inline_const_def_id).args(args)` uses the
-                    // proper type with NLL infer vars.
-                    let ty = tcx
-                        .typeck(self.mir_def)
-                        .node_type(tcx.local_def_id_to_hir_id(self.mir_def));
-                    let args = InlineConstArgs::new(
-                        tcx,
-                        InlineConstArgsParts { parent_args: identity_args, ty },
-                    )
-                    .args;
-                    let args = self.infcx.replace_free_regions_with_nll_infer_vars(
-                        NllRegionVariableOrigin::FreeRegion,
-                        args,
-                    );
-                    DefiningTy::InlineConst(self.mir_def.to_def_id(), args)
+                match tcx.def_kind(self.mir_def) {
+                    DefKind::InlineConst => {
+                        // This is required for `AscribeUserType` canonical query, which will call
+                        // `type_of(inline_const_def_id)`. That `type_of` would inject erased lifetimes
+                        // into borrowck, which is ICE #78174.
+                        //
+                        // As a workaround, inline consts have an additional generic param (`ty`
+                        // below), so that `type_of(inline_const_def_id).substs(substs)` uses the
+                        // proper type with NLL infer vars.
+                        //
+                        // Fetch the actual type from MIR, as `type_of` returns something useless
+                        // like `<const_ty>`.
+                        let body = tcx.mir_promoted(self.mir_def).0.borrow();
+                        let ty = body.local_decls[RETURN_PLACE].ty;
+                        let typeck_root_def_id = tcx.typeck_root_def_id(self.mir_def.to_def_id());
+                        let parent_args = GenericArgs::identity_for_item(tcx, typeck_root_def_id);
+                        let args =
+                            InlineConstArgs::new(tcx, InlineConstArgsParts { parent_args, ty })
+                                .args;
+                        let args = self.infcx.replace_free_regions_with_nll_infer_vars(
+                            NllRegionVariableOrigin::FreeRegion,
+                            args,
+                        );
+                        DefiningTy::InlineConst(self.mir_def.to_def_id(), args)
+                    }
+                    _ => {
+                        let identity_args =
+                            GenericArgs::identity_for_item(tcx, self.mir_def.to_def_id());
+                        let args = self.infcx.replace_free_regions_with_nll_infer_vars(
+                            NllRegionVariableOrigin::FreeRegion,
+                            identity_args,
+                        );
+                        DefiningTy::Const(self.mir_def.to_def_id(), args)
+                    }
                 }
             }
 

compiler/rustc_span/src/symbol.rs

@@ -2047,6 +2047,7 @@ symbols! {
         thumb2,
         thumb_mode: "thumb-mode",
         tmm_reg,
+        to_owned_method,
         to_string,
         to_vec,
         tool_attributes,

src/tools/clippy/clippy_utils/src/sym.rs

@@ -606,7 +606,6 @@ generate! {
     to_ne_bytes,
     to_os_string,
     to_owned,
-    to_owned_method,
     to_path_buf,
     to_string_method,
     to_uppercase,

tests/ui/issues/issue-44247.rs → tests/ui/associated-consts/assoc-const-and-type-same-name.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/44247
+
 //@ check-pass
 #![allow(dead_code)]
 trait T {

tests/ui/issues/issue-31267-additional.rs → tests/ui/associated-consts/assoc-const-in-array-initializer.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/31267
+
 //@ run-pass
 
 #[derive(Clone, Copy, Debug)]

tests/ui/issues/issue-24947.rs → tests/ui/associated-consts/assoc-const-in-array-size.rs

@@ -1,6 +1,6 @@
 //@ run-pass
-// #24947 ICE using a trait-associated const in an array size
-
+// Regression test for https://github.com/rust-lang/rust/issues/24947
+// ICE using a trait-associated const in an array size
 
 struct Foo;
 

tests/ui/issues/issue-25145.rs → tests/ui/associated-consts/assoc-const-in-static-array-size.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/25145
+
 //@ run-pass
 
 struct S;

tests/ui/issues/issue-42956.rs → tests/ui/associated-consts/assoc-const-through-assoc-type-path.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/42956
+
 //@ check-pass
 #![allow(dead_code)]
 

tests/ui/issues/issue-28586.rs → tests/ui/associated-consts/no-assoc-item-bytes-on-usize.rs

@@ -1,4 +1,4 @@
-// Regression test for issue #28586
+// Regression test for issue https://github.com/rust-lang/rust/issues/28586
 
 pub trait Foo {}
 impl Foo for [u8; usize::BYTES] {}

tests/ui/issues/issue-28586.stderr → tests/ui/associated-consts/no-assoc-item-bytes-on-usize.stderr

@@ -1,5 +1,5 @@
 error[E0599]: no associated function or constant named `BYTES` found for type `usize` in the current scope
-  --> $DIR/issue-28586.rs:4:26
+  --> $DIR/no-assoc-item-bytes-on-usize.rs:4:26
    |
 LL | impl Foo for [u8; usize::BYTES] {}
    |                          ^^^^^ associated function or constant not found in `usize`

tests/ui/issues/issue-34780.rs → tests/ui/associated-consts/trait-const-with-phantom-data-lifetime.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/34780
+
 //@ check-pass
 
 use std::marker::PhantomData;

tests/ui/issues/issue-43988.rs → tests/ui/attributes/attribute-on-wrong-item-inline-repr.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/43988
+
 #![feature(stmt_expr_attributes)]
 
 fn main() {

tests/ui/issues/issue-43988.stderr → tests/ui/attributes/attribute-on-wrong-item-inline-repr.stderr

@@ -1,13 +1,13 @@
 error: `#[inline]` attribute cannot be used on statements
-  --> $DIR/issue-43988.rs:5:5
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:7:5
    |
 LL |     #[inline]
    |     ^^^^^^^^^
    |
    = help: `#[inline]` can only be applied to functions
 
 error[E0539]: malformed `inline` attribute input
-  --> $DIR/issue-43988.rs:10:5
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:12:5
    |
 LL |     #[inline(XYZ)]
    |     ^^^^^^^^^---^^
@@ -28,15 +28,15 @@ LL +     #[inline]
    |
 
 error: `#[inline]` attribute cannot be used on statements
-  --> $DIR/issue-43988.rs:10:5
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:12:5
    |
 LL |     #[inline(XYZ)]
    |     ^^^^^^^^^^^^^^
    |
    = help: `#[inline]` can only be applied to functions
 
 error[E0552]: unrecognized representation hint
-  --> $DIR/issue-43988.rs:15:12
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:17:12
    |
 LL |     #[repr(nothing)]
    |            ^^^^^^^
@@ -45,7 +45,7 @@ LL |     #[repr(nothing)]
    = note: for more information, visit <https://doc.rust-lang.org/reference/type-layout.html?highlight=repr#representations>
 
 error[E0552]: unrecognized representation hint
-  --> $DIR/issue-43988.rs:19:12
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:21:12
    |
 LL |     #[repr(something_not_real)]
    |            ^^^^^^^^^^^^^^^^^^
@@ -54,15 +54,15 @@ LL |     #[repr(something_not_real)]
    = note: for more information, visit <https://doc.rust-lang.org/reference/type-layout.html?highlight=repr#representations>
 
 error[E0539]: malformed `repr` attribute input
-  --> $DIR/issue-43988.rs:25:5
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:27:5
    |
 LL |     #[repr]
    |     ^^^^^^^ expected this to be a list
    |
    = note: for more information, visit <https://doc.rust-lang.org/reference/type-layout.html#representations>
 
 error[E0539]: malformed `inline` attribute input
-  --> $DIR/issue-43988.rs:31:5
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:33:5
    |
 LL |     #[inline(ABC)]
    |     ^^^^^^^^^---^^
@@ -83,15 +83,15 @@ LL +     #[inline]
    |
 
 error: `#[inline]` attribute cannot be used on expressions
-  --> $DIR/issue-43988.rs:31:5
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:33:5
    |
 LL |     #[inline(ABC)]
    |     ^^^^^^^^^^^^^^
    |
    = help: `#[inline]` can only be applied to functions
 
 error[E0539]: malformed `repr` attribute input
-  --> $DIR/issue-43988.rs:36:14
+  --> $DIR/attribute-on-wrong-item-inline-repr.rs:38:14
    |
 LL |     let _z = #[repr] 1;
    |              ^^^^^^^ expected this to be a list

tests/ui/issues/issue-24434.rs → tests/ui/attributes/cfg-attr-feature-gate-and-rustc-dummy.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/24434
+
 //@ check-pass
 
 #![cfg_attr(true, feature(rustc_attrs))]

tests/ui/issues/issue-49632.rs → tests/ui/attributes/inline-attribute-on-closure.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/49632
+
 //@ run-pass
 #![feature(stmt_expr_attributes)]
 

tests/ui/issues/issue-45562.fixed → tests/ui/attributes/no-mangle-on-const-error.fixed

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/45562
+
 //@ run-rustfix
 
 #![deny(unused_attributes)]

tests/ui/issues/issue-45562.rs → tests/ui/attributes/no-mangle-on-const-error.rs

@@ -1,3 +1,5 @@
+//! Regression test for https://github.com/rust-lang/rust/issues/45562
+
 //@ run-rustfix
 
 #![deny(unused_attributes)]

tests/ui/issues/issue-45562.stderr → tests/ui/attributes/no-mangle-on-const-error.stderr

@@ -1,5 +1,5 @@
 error: const items should never be `#[no_mangle]`
-  --> $DIR/issue-45562.rs:5:14
+  --> $DIR/no-mangle-on-const-error.rs:7:14
    |
 LL | #[no_mangle] pub const RAH: usize = 5;
    |              ----------^^^^^^^^^^^^^^^