Auto merge of #96214 - Dylan-DPC:rollup-a5b4fow, r=Dylan-DPC

Rollup of 6 pull requests

Successful merges:

 - #94493 (Improved diagnostic on failure to meet send bound on future in a foreign crate)
 - #95809 (Fix typo in bootstrap.py)
 - #96086 (Remove `--extern-location` and all associated code)
 - #96089 (`alloc`: make `vec!` unavailable under `no_global_oom_handling`)
 - #96122 (Fix an invalid error for a suggestion to add a slice in pattern-matching)
 - #96142 (Stop using CRATE_DEF_INDEX outside of metadata encoding.)

Failed merges:

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

38 files changed, 83 insertions, 248 deletions

diff --git a/src/bootstrap/bootstrap.py b/src/bootstrap/bootstrap.py
index d437397045c..ac1c47524fd 100644
--- a/src/bootstrap/bootstrap.py
+++ b/src/bootstrap/bootstrap.py
@@ -817,7 +817,7 @@ class RustBuild(object):
         return os.path.join(self.bin_root(True), '.rustfmt-stamp')
 
     def llvm_stamp(self):
-        """Return the path for .rustfmt-stamp
+        """Return the path for .llvm-stamp
 
         >>> rb = RustBuild()
         >>> rb.build_dir = "build"
diff --git a/src/doc/unstable-book/src/compiler-flags/extern-location.md b/src/doc/unstable-book/src/compiler-flags/extern-location.md
deleted file mode 100644
index 1c80d5426bf..00000000000
--- a/src/doc/unstable-book/src/compiler-flags/extern-location.md
+++ /dev/null
@@ -1,31 +0,0 @@
-# `extern-location`
-
-MCP for this feature: [#303]
-
-[#303]: https://github.com/rust-lang/compiler-team/issues/303
-
-------------------------
-
-The `unused-extern-crates` lint reports when a crate was specified on the rustc
-command-line with `--extern name=path` but no symbols were referenced in it.
-This is useful to know, but it's hard to map that back to a specific place a user
-or tool could fix (ie, to remove the unused dependency).
-
-The `--extern-location` flag allows the build system to associate a location with
-the `--extern` option, which is then emitted as part of the diagnostics. This location
-is abstract and just round-tripped through rustc; the compiler never attempts to
-interpret it in any way.
-
-There are two supported forms of location: a bare string, or a blob of json:
-- `--extern-location foo=raw:Makefile:123` would associate the raw string `Makefile:123`
-- `--extern-location 'bar=json:{"target":"//my_project:library","dep":"//common:serde"}` would
-  associate the json structure with `--extern bar=<path>`, indicating which dependency of
-  which rule introduced the unused extern crate.
-
-This primarily intended to be used with tooling - for example a linter which can automatically
-remove unused dependencies - rather than being directly presented to users.
-
-`raw` locations are presented as part of the normal rendered diagnostics and included in
-the json form. `json` locations are only included in the json form of diagnostics,
-as a `tool_metadata` field. For `raw` locations `tool_metadata` is simply a json string,
-whereas `json` allows the rustc invoker to fully control its form and content.
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 21016afbf5f..a070cef2272 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -15,7 +15,7 @@ use rustc_attr as attr;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
-use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
+use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 use rustc_infer::infer::region_constraints::{Constraint, RegionConstraintData};
 use rustc_middle::middle::resolve_lifetime as rl;
 use rustc_middle::ty::fold::TypeFolder;
@@ -1975,7 +1975,7 @@ fn clean_extern_crate(
     // this is the ID of the `extern crate` statement
     let cnum = cx.tcx.extern_mod_stmt_cnum(krate.def_id).unwrap_or(LOCAL_CRATE);
     // this is the ID of the crate itself
-    let crate_def_id = DefId { krate: cnum, index: CRATE_DEF_INDEX };
+    let crate_def_id = cnum.as_def_id();
     let attrs = cx.tcx.hir().attrs(krate.hir_id());
     let ty_vis = cx.tcx.visibility(krate.def_id);
     let please_inline = ty_vis.is_public()
@@ -2094,7 +2094,7 @@ fn clean_use_statement(
     } else {
         if inline_attr.is_none() {
             if let Res::Def(DefKind::Mod, did) = path.res {
-                if !did.is_local() && did.index == CRATE_DEF_INDEX {
+                if !did.is_local() && did.is_crate_root() {
                     // if we're `pub use`ing an extern crate root, don't inline it unless we
                     // were specifically asked for it
                     denied = true;
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
index 4b473df155f..e30bc6e0a97 100644
--- a/src/librustdoc/clean/types.rs
+++ b/src/librustdoc/clean/types.rs
@@ -20,7 +20,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::thin_vec::ThinVec;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
-use rustc_hir::def_id::{CrateNum, DefId, DefIndex, CRATE_DEF_INDEX, LOCAL_CRATE};
+use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
 use rustc_hir::lang_items::LangItem;
 use rustc_hir::{BodyId, Mutability};
 use rustc_index::vec::IndexVec;
@@ -104,14 +104,6 @@ impl ItemId {
             ItemId::Primitive(_, krate) => krate,
         }
     }
-
-    #[inline]
-    crate fn index(self) -> Option<DefIndex> {
-        match self {
-            ItemId::DefId(id) => Some(id.index),
-            _ => None,
-        }
-    }
 }
 
 impl From<DefId> for ItemId {
@@ -160,7 +152,7 @@ impl ExternalCrate {
 
     #[inline]
     crate fn def_id(&self) -> DefId {
-        DefId { krate: self.crate_num, index: CRATE_DEF_INDEX }
+        self.crate_num.as_def_id()
     }
 
     crate fn src(&self, tcx: TyCtxt<'_>) -> FileName {
@@ -217,7 +209,7 @@ impl ExternalCrate {
 
         // Failing that, see if there's an attribute specifying where to find this
         // external crate
-        let did = DefId { krate: self.crate_num, index: CRATE_DEF_INDEX };
+        let did = self.crate_num.as_def_id();
         tcx.get_attrs(did)
             .lists(sym::doc)
             .filter(|a| a.has_name(sym::html_root_url))
@@ -559,7 +551,7 @@ impl Item {
     }
 
     crate fn is_crate(&self) -> bool {
-        self.is_mod() && self.item_id.as_def_id().map_or(false, |did| did.index == CRATE_DEF_INDEX)
+        self.is_mod() && self.item_id.as_def_id().map_or(false, |did| did.is_crate_root())
     }
     crate fn is_mod(&self) -> bool {
         self.type_() == ItemType::Module
diff --git a/src/librustdoc/formats/cache.rs b/src/librustdoc/formats/cache.rs
index 06e7c9e763d..b4d2772b31d 100644
--- a/src/librustdoc/formats/cache.rs
+++ b/src/librustdoc/formats/cache.rs
@@ -1,7 +1,7 @@
 use std::mem;
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX};
+use rustc_hir::def_id::{CrateNum, DefId};
 use rustc_middle::middle::privacy::AccessLevels;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::{sym, Symbol};
@@ -302,7 +302,7 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
                     // A crate has a module at its root, containing all items,
                     // which should not be indexed. The crate-item itself is
                     // inserted later on when serializing the search-index.
-                    if item.item_id.index().map_or(false, |idx| idx != CRATE_DEF_INDEX) {
+                    if item.item_id.as_def_id().map_or(false, |idx| !idx.is_crate_root()) {
                         let desc = item.doc_value().map_or_else(String::new, |x| {
                             short_markdown_summary(x.as_str(), &item.link_names(self.cache))
                         });
diff --git a/src/librustdoc/html/format.rs b/src/librustdoc/html/format.rs
index 55b0028180f..6954e2363f5 100644
--- a/src/librustdoc/html/format.rs
+++ b/src/librustdoc/html/format.rs
@@ -18,7 +18,6 @@ use rustc_hir::def_id::DefId;
 use rustc_middle::ty;
 use rustc_middle::ty::DefIdTree;
 use rustc_middle::ty::TyCtxt;
-use rustc_span::def_id::CRATE_DEF_INDEX;
 use rustc_span::{sym, Symbol};
 use rustc_target::spec::abi::Abi;
 
@@ -1312,7 +1311,7 @@ impl clean::Visibility {
                 //                 visibility, so it shouldn't matter.
                 let parent_module = find_nearest_parent_module(cx.tcx(), item_did.expect_def_id());
 
-                if vis_did.index == CRATE_DEF_INDEX {
+                if vis_did.is_crate_root() {
                     "pub(crate) ".to_owned()
                 } else if parent_module == Some(vis_did) {
                     // `pub(in foo)` where `foo` is the parent module
@@ -1360,7 +1359,7 @@ impl clean::Visibility {
                 //                 visibility, so it shouldn't matter.
                 let parent_module = find_nearest_parent_module(tcx, item_did);
 
-                if vis_did.index == CRATE_DEF_INDEX {
+                if vis_did.is_crate_root() {
                     "pub(crate) ".to_owned()
                 } else if parent_module == Some(vis_did) {
                     // `pub(in foo)` where `foo` is the parent module
diff --git a/src/librustdoc/json/conversions.rs b/src/librustdoc/json/conversions.rs
index 0b5fb480595..56b02cd8480 100644
--- a/src/librustdoc/json/conversions.rs
+++ b/src/librustdoc/json/conversions.rs
@@ -10,7 +10,6 @@ use std::fmt;
 use rustc_ast::ast;
 use rustc_hir::{def::CtorKind, def_id::DefId};
 use rustc_middle::ty::{self, TyCtxt};
-use rustc_span::def_id::CRATE_DEF_INDEX;
 use rustc_span::Pos;
 use rustc_target::spec::abi::Abi as RustcAbi;
 
@@ -83,7 +82,7 @@ impl JsonRenderer<'_> {
         match v {
             Public => Visibility::Public,
             Inherited => Visibility::Default,
-            Restricted(did) if did.index == CRATE_DEF_INDEX => Visibility::Crate,
+            Restricted(did) if did.is_crate_root() => Visibility::Crate,
             Restricted(did) => Visibility::Restricted {
                 parent: from_item_id(did.into()),
                 path: self.tcx.def_path(did).to_string_no_crate_verbose(),
diff --git a/src/librustdoc/visit_lib.rs b/src/librustdoc/visit_lib.rs
index 5bcec779bc0..9723cdbe334 100644
--- a/src/librustdoc/visit_lib.rs
+++ b/src/librustdoc/visit_lib.rs
@@ -1,6 +1,6 @@
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::def::{DefKind, Res};
-use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX};
+use rustc_hir::def_id::{CrateNum, DefId};
 use rustc_middle::middle::privacy::{AccessLevel, AccessLevels};
 use rustc_middle::ty::TyCtxt;
 
@@ -29,7 +29,7 @@ impl<'a, 'tcx> LibEmbargoVisitor<'a, 'tcx> {
     }
 
     crate fn visit_lib(&mut self, cnum: CrateNum) {
-        let did = DefId { krate: cnum, index: CRATE_DEF_INDEX };
+        let did = cnum.as_def_id();
         self.update(did, Some(AccessLevel::Public));
         self.visit_mod(did);
     }
diff --git a/src/test/ui/async-await/issues/issue-67893.rs b/src/test/ui/async-await/issues/issue-67893.rs
index 8b53408d758..d73772e5fa0 100644
--- a/src/test/ui/async-await/issues/issue-67893.rs
+++ b/src/test/ui/async-await/issues/issue-67893.rs
@@ -7,5 +7,5 @@ fn g(_: impl Send) {}
 
 fn main() {
     g(issue_67893::run())
-    //~^ ERROR generator cannot be sent between threads safely
+    //~^ ERROR future cannot be sent between threads safely
 }
diff --git a/src/test/ui/async-await/issues/issue-67893.stderr b/src/test/ui/async-await/issues/issue-67893.stderr
index 0aa0d5d7ccd..316b6d06f93 100644
--- a/src/test/ui/async-await/issues/issue-67893.stderr
+++ b/src/test/ui/async-await/issues/issue-67893.stderr
@@ -1,10 +1,22 @@
-error: generator cannot be sent between threads safely
+error: future cannot be sent between threads safely
   --> $DIR/issue-67893.rs:9:7
    |
 LL |     g(issue_67893::run())
-   |       ^^^^^^^^^^^^^^^^^^ generator is not `Send`
+   |       ^^^^^^^^^^^^^^^^^^ future is not `Send`
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `MutexGuard<'_, ()>`
+note: future is not `Send` as this value is used across an await
+  --> $DIR/auxiliary/issue_67893.rs:9:26
+   |
+LL |     f(*x.lock().unwrap()).await;
+   |        ----------------- ^^^^^^ await occurs here, with `x.lock().unwrap()` maybe used later
+   |        |
+   |        has type `MutexGuard<'_, ()>` which is not `Send`
+note: `x.lock().unwrap()` is later dropped here
+  --> $DIR/auxiliary/issue_67893.rs:9:32
+   |
+LL |     f(*x.lock().unwrap()).await;
+   |                                ^
 note: required by a bound in `g`
   --> $DIR/issue-67893.rs:6:14
    |
diff --git a/src/test/ui/suggestions/pattern-struct-with-slice-vec-field.rs b/src/test/ui/suggestions/pattern-struct-with-slice-vec-field.rs
new file mode 100644
index 00000000000..5b223a91f50
--- /dev/null
+++ b/src/test/ui/suggestions/pattern-struct-with-slice-vec-field.rs
@@ -0,0 +1,35 @@
+use std::ops::Deref;
+
+struct Foo {
+    v: Vec<u32>,
+}
+
+struct Bar {
+    v: Vec<u32>,
+}
+
+impl Deref for Bar {
+    type Target = Vec<u32>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.v
+    }
+}
+
+fn f(foo: &Foo) {
+    match foo {
+        Foo { v: [1, 2] } => {}
+        //~^ ERROR expected an array or slice, found `Vec<u32>
+        _ => {}
+    }
+}
+
+fn bar(bar: &Bar) {
+    match bar {
+        Bar { v: [1, 2] } => {}
+        //~^ ERROR expected an array or slice, found `Vec<u32>
+        _ => {}
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/suggestions/pattern-struct-with-slice-vec-field.stderr b/src/test/ui/suggestions/pattern-struct-with-slice-vec-field.stderr
new file mode 100644
index 00000000000..5b48a8b18a5
--- /dev/null
+++ b/src/test/ui/suggestions/pattern-struct-with-slice-vec-field.stderr
@@ -0,0 +1,15 @@
+error[E0529]: expected an array or slice, found `Vec<u32>`
+  --> $DIR/pattern-struct-with-slice-vec-field.rs:21:18
+   |
+LL |         Foo { v: [1, 2] } => {}
+   |                  ^^^^^^ pattern cannot match with input type `Vec<u32>`
+
+error[E0529]: expected an array or slice, found `Vec<u32>`
+  --> $DIR/pattern-struct-with-slice-vec-field.rs:29:18
+   |
+LL |         Bar { v: [1, 2] } => {}
+   |                  ^^^^^^ pattern cannot match with input type `Vec<u32>`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0529`.
diff --git a/src/test/ui/unused-crate-deps/extern-loc-bad-loctype.rs b/src/test/ui/unused-crate-deps/extern-loc-bad-loctype.rs
deleted file mode 100644
index e69df0359fd..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-bad-loctype.rs
+++ /dev/null
@@ -1,8 +0,0 @@
-// --extern-location with bad location type
-
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar=badloc:in-the-test-file -Z unstable-options
-
-#![warn(unused_crate_dependencies)]
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-bad-loctype.stderr b/src/test/ui/unused-crate-deps/extern-loc-bad-loctype.stderr
deleted file mode 100644
index 12378f12557..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-bad-loctype.stderr
+++ /dev/null
@@ -1,2 +0,0 @@
-error: unknown location type `badloc`: use `raw` or `json`
-
diff --git a/src/test/ui/unused-crate-deps/extern-loc-defl-json.rs b/src/test/ui/unused-crate-deps/extern-loc-defl-json.rs
deleted file mode 100644
index a023f535b81..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-defl-json.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-// Default extern location from name and path if one isn't specified
-
-// check-pass
-// aux-crate:bar=bar.rs
-// compile-flags:--error-format json
-
-#![warn(unused_crate_dependencies)]
-//~^ WARNING external crate `bar` unused in
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-defl-json.stderr b/src/test/ui/unused-crate-deps/extern-loc-defl-json.stderr
deleted file mode 100644
index cee3f6c1495..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-defl-json.stderr
+++ /dev/null
@@ -1,17 +0,0 @@
-{"message":"external crate `bar` unused in `extern_loc_defl_json`: remove the dependency or add `use bar as _;`","code":{"code":"unused_crate_dependencies","explanation":null},"level":"warning","spans":[{"file_name":"$DIR/extern-loc-defl-json.rs","byte_start":146,"byte_end":146,"line_start":7,"line_end":7,"column_start":1,"column_end":1,"is_primary":true,"text":[{"text":"#![warn(unused_crate_dependencies)]","highlight_start":1,"highlight_end":1}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"the lint level is defined here","code":null,"level":"note","spans":[{"file_name":"$DIR/extern-loc-defl-json.rs","byte_start":154,"byte_end":179,"line_start":7,"line_end":7,"column_start":9,"column_end":34,"is_primary":true,"text":[{"text":"#![warn(unused_crate_dependencies)]","highlight_start":9,"highlight_end":34}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[],"rendered":null},{"message":"remove unnecessary dependency `bar`","code":null,"level":"help","spans":[],"children":[],"rendered":null},{"message":"json extern location","code":null,"level":"help","spans":[],"children":[],"rendered":null,"tool_metadata":{"name":"bar"}}],"rendered":"warning: external crate `bar` unused in `extern_loc_defl_json`: remove the dependency or add `use bar as _;`
-  --> $DIR/extern-loc-defl-json.rs:7:1
-   |
-LL | #![warn(unused_crate_dependencies)]
-   | ^
-   |
-note: the lint level is defined here
-  --> $DIR/extern-loc-defl-json.rs:7:9
-   |
-LL | #![warn(unused_crate_dependencies)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
-   = help: remove unnecessary dependency `bar`
-
-"}
-{"message":"1 warning emitted","code":null,"level":"warning","spans":[],"children":[],"rendered":"warning: 1 warning emitted
-
-"}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-json-bad-json.rs b/src/test/ui/unused-crate-deps/extern-loc-json-bad-json.rs
deleted file mode 100644
index aee6233e428..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-json-bad-json.rs
+++ /dev/null
@@ -1,8 +0,0 @@
-// --extern-location with a raw reference
-
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar=json:[{"malformed -Z unstable-options
-
-#![warn(unused_crate_dependencies)]
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-json-bad-json.stderr b/src/test/ui/unused-crate-deps/extern-loc-json-bad-json.stderr
deleted file mode 100644
index 20d606372e0..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-json-bad-json.stderr
+++ /dev/null
@@ -1,2 +0,0 @@
-error: `--extern-location`: malformed json location `[{"malformed`
-
diff --git a/src/test/ui/unused-crate-deps/extern-loc-json-json.rs b/src/test/ui/unused-crate-deps/extern-loc-json-json.rs
deleted file mode 100644
index c7988cd469e..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-json-json.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-// --extern-location with a raw reference
-
-// check-pass
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar=json:{"key":123,"value":{}} --error-format json -Z unstable-options
-
-#![warn(unused_crate_dependencies)]
-//~^ WARNING external crate `bar` unused in
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-json-json.stderr b/src/test/ui/unused-crate-deps/extern-loc-json-json.stderr
deleted file mode 100644
index 001ec6a2554..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-json-json.stderr
+++ /dev/null
@@ -1,17 +0,0 @@
-{"message":"external crate `bar` unused in `extern_loc_json_json`: remove the dependency or add `use bar as _;`","code":{"code":"unused_crate_dependencies","explanation":null},"level":"warning","spans":[{"file_name":"$DIR/extern-loc-json-json.rs","byte_start":189,"byte_end":189,"line_start":7,"line_end":7,"column_start":1,"column_end":1,"is_primary":true,"text":[{"text":"#![warn(unused_crate_dependencies)]","highlight_start":1,"highlight_end":1}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"the lint level is defined here","code":null,"level":"note","spans":[{"file_name":"$DIR/extern-loc-json-json.rs","byte_start":197,"byte_end":222,"line_start":7,"line_end":7,"column_start":9,"column_end":34,"is_primary":true,"text":[{"text":"#![warn(unused_crate_dependencies)]","highlight_start":9,"highlight_end":34}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[],"rendered":null},{"message":"remove unnecessary dependency `bar`","code":null,"level":"help","spans":[],"children":[],"rendered":null},{"message":"json extern location","code":null,"level":"help","spans":[],"children":[],"rendered":null,"tool_metadata":{"key":123,"value":{}}}],"rendered":"warning: external crate `bar` unused in `extern_loc_json_json`: remove the dependency or add `use bar as _;`
-  --> $DIR/extern-loc-json-json.rs:7:1
-   |
-LL | #![warn(unused_crate_dependencies)]
-   | ^
-   |
-note: the lint level is defined here
-  --> $DIR/extern-loc-json-json.rs:7:9
-   |
-LL | #![warn(unused_crate_dependencies)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
-   = help: remove unnecessary dependency `bar`
-
-"}
-{"message":"1 warning emitted","code":null,"level":"warning","spans":[],"children":[],"rendered":"warning: 1 warning emitted
-
-"}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-json.rs b/src/test/ui/unused-crate-deps/extern-loc-json.rs
deleted file mode 100644
index c0d76c86b89..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-json.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-// --extern-location with a raw reference
-
-// check-pass
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar=json:{"key":123,"value":{}} -Z unstable-options
-
-#![warn(unused_crate_dependencies)]
-//~^ WARNING external crate `bar` unused in
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-json.stderr b/src/test/ui/unused-crate-deps/extern-loc-json.stderr
deleted file mode 100644
index a6bbc0da1c6..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-json.stderr
+++ /dev/null
@@ -1,15 +0,0 @@
-warning: external crate `bar` unused in `extern_loc_json`: remove the dependency or add `use bar as _;`
-  --> $DIR/extern-loc-json.rs:7:1
-   |
-LL | #![warn(unused_crate_dependencies)]
-   | ^
-   |
-note: the lint level is defined here
-  --> $DIR/extern-loc-json.rs:7:9
-   |
-LL | #![warn(unused_crate_dependencies)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
-   = help: remove unnecessary dependency `bar`
-
-warning: 1 warning emitted
-
diff --git a/src/test/ui/unused-crate-deps/extern-loc-missing-loc.rs b/src/test/ui/unused-crate-deps/extern-loc-missing-loc.rs
deleted file mode 100644
index 6ac558974d0..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-missing-loc.rs
+++ /dev/null
@@ -1,8 +0,0 @@
-// --extern-location with a raw reference
-
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar -Zunstable-options
-
-#![warn(unused_crate_dependencies)]
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-missing-loc.stderr b/src/test/ui/unused-crate-deps/extern-loc-missing-loc.stderr
deleted file mode 100644
index 4584fbfb67f..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-missing-loc.stderr
+++ /dev/null
@@ -1,2 +0,0 @@
-error: `--extern-location`: specify location for extern crate `bar`
-
diff --git a/src/test/ui/unused-crate-deps/extern-loc-missing-loctype.rs b/src/test/ui/unused-crate-deps/extern-loc-missing-loctype.rs
deleted file mode 100644
index 3590b9c2812..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-missing-loctype.rs
+++ /dev/null
@@ -1,8 +0,0 @@
-// --extern-location with no type
-
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar=missing-loc-type -Z unstable-options
-
-#![warn(unused_crate_dependencies)]
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-missing-loctype.stderr b/src/test/ui/unused-crate-deps/extern-loc-missing-loctype.stderr
deleted file mode 100644
index d0c36ebeb14..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-missing-loctype.stderr
+++ /dev/null
@@ -1,2 +0,0 @@
-error: unknown location type `missing-loc-type`: use `raw` or `json`
-
diff --git a/src/test/ui/unused-crate-deps/extern-loc-raw-json.rs b/src/test/ui/unused-crate-deps/extern-loc-raw-json.rs
deleted file mode 100644
index 64c3d77ce08..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-raw-json.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-// --extern-location with a raw reference
-
-// check-pass
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar=raw:in-the-test-file --error-format json -Z unstable-options
-
-#![warn(unused_crate_dependencies)]
-//~^ WARNING external crate `bar` unused in
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-raw-json.stderr b/src/test/ui/unused-crate-deps/extern-loc-raw-json.stderr
deleted file mode 100644
index 4083bd51835..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-raw-json.stderr
+++ /dev/null
@@ -1,17 +0,0 @@
-{"message":"external crate `bar` unused in `extern_loc_raw_json`: remove the dependency or add `use bar as _;`","code":{"code":"unused_crate_dependencies","explanation":null},"level":"warning","spans":[{"file_name":"$DIR/extern-loc-raw-json.rs","byte_start":182,"byte_end":182,"line_start":7,"line_end":7,"column_start":1,"column_end":1,"is_primary":true,"text":[{"text":"#![warn(unused_crate_dependencies)]","highlight_start":1,"highlight_end":1}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[{"message":"the lint level is defined here","code":null,"level":"note","spans":[{"file_name":"$DIR/extern-loc-raw-json.rs","byte_start":190,"byte_end":215,"line_start":7,"line_end":7,"column_start":9,"column_end":34,"is_primary":true,"text":[{"text":"#![warn(unused_crate_dependencies)]","highlight_start":9,"highlight_end":34}],"label":null,"suggested_replacement":null,"suggestion_applicability":null,"expansion":null}],"children":[],"rendered":null},{"message":"remove unnecessary dependency `bar` at `in-the-test-file`","code":null,"level":"help","spans":[],"children":[],"rendered":null},{"message":"raw extern location","code":null,"level":"help","spans":[{"file_name":"$DIR/extern-loc-raw-json.rs","byte_start":0,"byte_end":0,"line_start":1,"line_end":1,"column_start":1,"column_end":1,"is_primary":true,"text":[],"label":null,"suggested_replacement":"in-the-test-file","suggestion_applicability":"Unspecified","expansion":null}],"children":[],"rendered":null},{"message":"json extern location","code":null,"level":"help","spans":[],"children":[],"rendered":null,"tool_metadata":"in-the-test-file"}],"rendered":"warning: external crate `bar` unused in `extern_loc_raw_json`: remove the dependency or add `use bar as _;`
-  --> $DIR/extern-loc-raw-json.rs:7:1
-   |
-LL | #![warn(unused_crate_dependencies)]
-   | ^
-   |
-note: the lint level is defined here
-  --> $DIR/extern-loc-raw-json.rs:7:9
-   |
-LL | #![warn(unused_crate_dependencies)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
-   = help: remove unnecessary dependency `bar` at `in-the-test-file`
-
-"}
-{"message":"1 warning emitted","code":null,"level":"warning","spans":[],"children":[],"rendered":"warning: 1 warning emitted
-
-"}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-raw-missing-loc.rs b/src/test/ui/unused-crate-deps/extern-loc-raw-missing-loc.rs
deleted file mode 100644
index a9e7afbda31..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-raw-missing-loc.rs
+++ /dev/null
@@ -1,8 +0,0 @@
-// --extern-location with a raw reference
-
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar=raw -Z unstable-options
-
-#![warn(unused_crate_dependencies)]
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-raw-missing-loc.stderr b/src/test/ui/unused-crate-deps/extern-loc-raw-missing-loc.stderr
deleted file mode 100644
index 4b51266e4f6..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-raw-missing-loc.stderr
+++ /dev/null
@@ -1,2 +0,0 @@
-error: `--extern-location`: missing `raw` location
-
diff --git a/src/test/ui/unused-crate-deps/extern-loc-raw.rs b/src/test/ui/unused-crate-deps/extern-loc-raw.rs
deleted file mode 100644
index 27d0975d01a..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-raw.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-// --extern-location with a raw reference
-
-// check-pass
-// aux-crate:bar=bar.rs
-// compile-flags:--extern-location bar=raw:in-the-test-file -Z unstable-options
-
-#![warn(unused_crate_dependencies)]
-//~^ WARNING external crate `bar` unused in
-
-fn main() {}
diff --git a/src/test/ui/unused-crate-deps/extern-loc-raw.stderr b/src/test/ui/unused-crate-deps/extern-loc-raw.stderr
deleted file mode 100644
index 2cdd0055866..00000000000
--- a/src/test/ui/unused-crate-deps/extern-loc-raw.stderr
+++ /dev/null
@@ -1,15 +0,0 @@
-warning: external crate `bar` unused in `extern_loc_raw`: remove the dependency or add `use bar as _;`
-  --> $DIR/extern-loc-raw.rs:7:1
-   |
-LL | #![warn(unused_crate_dependencies)]
-   | ^
-   |
-note: the lint level is defined here
-  --> $DIR/extern-loc-raw.rs:7:9
-   |
-LL | #![warn(unused_crate_dependencies)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
-   = help: remove unnecessary dependency `bar` at `in-the-test-file`
-
-warning: 1 warning emitted
-
diff --git a/src/test/ui/unused-crate-deps/libfib.stderr b/src/test/ui/unused-crate-deps/libfib.stderr
index 479f51bff46..15833126bd6 100644
--- a/src/test/ui/unused-crate-deps/libfib.stderr
+++ b/src/test/ui/unused-crate-deps/libfib.stderr
@@ -5,7 +5,6 @@ LL | pub fn fib(n: u32) -> Vec<u32> {
    | ^
    |
    = note: requested on the command line with `-W unused-crate-dependencies`
-   = help: remove unnecessary dependency `bar`
 
 warning: 1 warning emitted
 
diff --git a/src/test/ui/unused-crate-deps/unused-aliases.stderr b/src/test/ui/unused-crate-deps/unused-aliases.stderr
index 1142d156d0e..c8c6c4507b0 100644
--- a/src/test/ui/unused-crate-deps/unused-aliases.stderr
+++ b/src/test/ui/unused-crate-deps/unused-aliases.stderr
@@ -9,7 +9,6 @@ note: the lint level is defined here
    |
 LL | #![warn(unused_crate_dependencies)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^
-   = help: remove unnecessary dependency `barbar`
 
 warning: 1 warning emitted
 
diff --git a/src/test/ui/unused-crate-deps/warn-attr.stderr b/src/test/ui/unused-crate-deps/warn-attr.stderr
index 29667d9525c..0d38315704b 100644
--- a/src/test/ui/unused-crate-deps/warn-attr.stderr
+++ b/src/test/ui/unused-crate-deps/warn-attr.stderr
@@ -9,7 +9,6 @@ note: the lint level is defined here
    |
 LL | #![warn(unused_crate_dependencies)]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^
-   = help: remove unnecessary dependency `bar`
 
 warning: 1 warning emitted
 
diff --git a/src/test/ui/unused-crate-deps/warn-cmdline-static.stderr b/src/test/ui/unused-crate-deps/warn-cmdline-static.stderr
index 2c0c9215129..65956461d64 100644
--- a/src/test/ui/unused-crate-deps/warn-cmdline-static.stderr
+++ b/src/test/ui/unused-crate-deps/warn-cmdline-static.stderr
@@ -5,7 +5,6 @@ LL | fn main() {}
    | ^
    |
    = note: requested on the command line with `-W unused-crate-dependencies`
-   = help: remove unnecessary dependency `bar`
 
 warning: 1 warning emitted
 
diff --git a/src/test/ui/unused-crate-deps/warn-cmdline.stderr b/src/test/ui/unused-crate-deps/warn-cmdline.stderr
index 2cd49218f5a..ea675ba9a1e 100644
--- a/src/test/ui/unused-crate-deps/warn-cmdline.stderr
+++ b/src/test/ui/unused-crate-deps/warn-cmdline.stderr
@@ -5,7 +5,6 @@ LL | fn main() {}
    | ^
    |
    = note: requested on the command line with `-W unused-crate-dependencies`
-   = help: remove unnecessary dependency `bar`
 
 warning: 1 warning emitted
 
diff --git a/src/tools/clippy/clippy_lints/src/missing_doc.rs b/src/tools/clippy/clippy_lints/src/missing_doc.rs
index fc0483a929a..5816a95dceb 100644
--- a/src/tools/clippy/clippy_lints/src/missing_doc.rs
+++ b/src/tools/clippy/clippy_lints/src/missing_doc.rs
@@ -10,7 +10,7 @@ use clippy_utils::diagnostics::span_lint;
 use rustc_ast::ast;
 use rustc_hir as hir;
 use rustc_lint::{LateContext, LateLintPass, LintContext};
-use rustc_middle::ty;
+use rustc_middle::ty::{self, DefIdTree};
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::def_id::CRATE_DEF_ID;
 use rustc_span::source_map::Span;
@@ -114,8 +114,8 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc {
             hir::ItemKind::Fn(..) => {
                 // ignore main()
                 if it.ident.name == sym::main {
-                    let def_key = cx.tcx.hir().def_key(it.def_id);
-                    if def_key.parent == Some(hir::def_id::CRATE_DEF_INDEX) {
+                    let at_root = cx.tcx.local_parent(it.def_id) == Some(CRATE_DEF_ID);
+                    if at_root {
                         return;
                     }
                 }