Auto merge of #101167 - matthiaskrgr:rollup-yt3jdmp, r=matthiaskrgr

Rollup of 7 pull requests

Successful merges:

 - #100898 (Do not report too many expr field candidates)
 - #101056 (Add the syntax of references to their documentation summary.)
 - #101106 (Rustdoc-Json: Retain Stripped Modules when they are imported, not when they have items)
 - #101131 (CTFE: exposing pointers and calling extern fn is just impossible)
 - #101141 (Simplify `get_trait_ref` fn used for `virtual_function_elimination`)
 - #101146 (Various changes to logging of borrowck-related code)
 - #101156 (Remove `Sync` requirement from lint pass objects)

Failed merges:

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

19 files changed, 191 insertions, 31 deletions

diff --git a/src/etc/check_missing_items.py b/src/etc/check_missing_items.py
index ce06a79a21c..025f320e3a1 100644
--- a/src/etc/check_missing_items.py
+++ b/src/etc/check_missing_items.py
@@ -187,3 +187,9 @@ while work_list:
             check_generic_bound(bound)
         if item["inner"]["default"]:
             check_type(item["inner"]["default"])
+    elif item["kind"] == "import":
+        if item["inner"]["id"]:
+            inner_id = item["inner"]["id"]
+            assert valid_id(inner_id)
+            if inner_id in crate["index"] and inner_id not in visited:
+                work_list.add(inner_id)
diff --git a/src/librustdoc/json/conversions.rs b/src/librustdoc/json/conversions.rs
index c4e8b6f5f84..20b9eb1c27e 100644
--- a/src/librustdoc/json/conversions.rs
+++ b/src/librustdoc/json/conversions.rs
@@ -46,10 +46,14 @@ impl JsonRenderer<'_> {
             clean::KeywordItem => return None,
             clean::StrippedItem(ref inner) => {
                 match &**inner {
-                    // We document non-empty stripped modules as with `Module::is_stripped` set to
+                    // We document stripped modules as with `Module::is_stripped` set to
                     // `true`, to prevent contained items from being orphaned for downstream users,
                     // as JSON does no inlining.
-                    clean::ModuleItem(m) if !m.items.is_empty() => from_clean_item(item, self.tcx),
+                    clean::ModuleItem(_)
+                        if self.imported_items.contains(&item_id.expect_def_id()) =>
+                    {
+                        from_clean_item(item, self.tcx)
+                    }
                     _ => return None,
                 }
             }
diff --git a/src/librustdoc/json/import_finder.rs b/src/librustdoc/json/import_finder.rs
new file mode 100644
index 00000000000..c5c687df74f
--- /dev/null
+++ b/src/librustdoc/json/import_finder.rs
@@ -0,0 +1,38 @@
+use rustc_data_structures::fx::FxHashSet;
+use rustc_hir::def_id::DefId;
+
+use crate::{
+    clean::{self, Import, ImportSource, Item},
+    fold::DocFolder,
+};
+
+/// Get the id's of all items that are `pub use`d in the crate.
+///
+/// We need this to know if a stripped module is `pub use mod::*`, to decide
+/// if it needs to be kept in the index, despite being stripped.
+///
+/// See [#100973](https://github.com/rust-lang/rust/issues/100973) and
+/// [#101103](https://github.com/rust-lang/rust/issues/101103) for times when
+/// this information is needed.
+pub(crate) fn get_imports(krate: clean::Crate) -> (clean::Crate, FxHashSet<DefId>) {
+    let mut finder = ImportFinder { imported: FxHashSet::default() };
+    let krate = finder.fold_crate(krate);
+    (krate, finder.imported)
+}
+
+struct ImportFinder {
+    imported: FxHashSet<DefId>,
+}
+
+impl DocFolder for ImportFinder {
+    fn fold_item(&mut self, i: Item) -> Option<Item> {
+        match *i.kind {
+            clean::ImportItem(Import { source: ImportSource { did: Some(did), .. }, .. }) => {
+                self.imported.insert(did);
+                Some(i)
+            }
+
+            _ => Some(self.fold_item_recur(i)),
+        }
+    }
+}
diff --git a/src/librustdoc/json/mod.rs b/src/librustdoc/json/mod.rs
index b78f8f2b4f1..6a1409c7394 100644
--- a/src/librustdoc/json/mod.rs
+++ b/src/librustdoc/json/mod.rs
@@ -5,6 +5,7 @@
 //! docs for usage and details.
 
 mod conversions;
+mod import_finder;
 
 use std::cell::RefCell;
 use std::fs::{create_dir_all, File};
@@ -12,7 +13,7 @@ use std::io::{BufWriter, Write};
 use std::path::PathBuf;
 use std::rc::Rc;
 
-use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::Session;
@@ -39,6 +40,7 @@ pub(crate) struct JsonRenderer<'tcx> {
     /// The directory where the blob will be written to.
     out_path: PathBuf,
     cache: Rc<Cache>,
+    imported_items: FxHashSet<DefId>,
 }
 
 impl<'tcx> JsonRenderer<'tcx> {
@@ -159,12 +161,16 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
         tcx: TyCtxt<'tcx>,
     ) -> Result<(Self, clean::Crate), Error> {
         debug!("Initializing json renderer");
+
+        let (krate, imported_items) = import_finder::get_imports(krate);
+
         Ok((
             JsonRenderer {
                 tcx,
                 index: Rc::new(RefCell::new(FxHashMap::default())),
                 out_path: options.output,
                 cache: Rc::new(cache),
+                imported_items,
             },
             krate,
         ))
diff --git a/src/test/rustdoc-json/reexport/glob_collision.rs b/src/test/rustdoc-json/reexport/glob_collision.rs
new file mode 100644
index 00000000000..f91144dbfad
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/glob_collision.rs
@@ -0,0 +1,28 @@
+// Regression test for https://github.com/rust-lang/rust/issues/100973
+
+#![feature(no_core)]
+#![no_core]
+
+// @set m1 = "$.index[*][?(@.name == 'm1' && @.kind == 'module')].id"
+// @is "$.index[*][?(@.name == 'm1' && @.kind == 'module')].inner.items" []
+// @is "$.index[*][?(@.name == 'm1' && @.kind == 'module')].inner.is_stripped" true
+mod m1 {
+    pub fn f() {}
+}
+// @set m2 = "$.index[*][?(@.name == 'm2' && @.kind == 'module')].id"
+// @is "$.index[*][?(@.name == 'm2' && @.kind == 'module')].inner.items" []
+// @is "$.index[*][?(@.name == 'm2' && @.kind == 'module')].inner.is_stripped" true
+mod m2 {
+    pub fn f(_: u8) {}
+}
+
+// @set m1_use = "$.index[*][?(@.inner.name=='m1')].id"
+// @is "$.index[*][?(@.inner.name=='m1')].inner.id" $m1
+// @is "$.index[*][?(@.inner.name=='m1')].inner.glob" true
+pub use m1::*;
+// @set m2_use = "$.index[*][?(@.inner.name=='m2')].id"
+// @is "$.index[*][?(@.inner.name=='m2')].inner.id" $m2
+// @is "$.index[*][?(@.inner.name=='m2')].inner.glob" true
+pub use m2::*;
+
+// @ismany "$.index[*][?(@.inner.is_crate==true)].inner.items[*]" $m1_use $m2_use
diff --git a/src/test/rustdoc-json/reexport/glob_empty_mod.rs b/src/test/rustdoc-json/reexport/glob_empty_mod.rs
new file mode 100644
index 00000000000..da68228352c
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/glob_empty_mod.rs
@@ -0,0 +1,8 @@
+// Regression test for https://github.com/rust-lang/rust/issues/100973
+
+// @is "$.index[*][?(@.name=='m1' && @.kind == 'module')].inner.is_stripped" true
+// @set m1 = "$.index[*][?(@.name=='m1')].id"
+mod m1 {}
+
+// @is "$.index[*][?(@.inner.name=='m1' && @.kind=='import')].inner.id" $m1
+pub use m1::*;
diff --git a/src/test/rustdoc-json/reexport/in_root_and_mod.rs b/src/test/rustdoc-json/reexport/in_root_and_mod.rs
index 68cb694f499..7b97ebf2129 100644
--- a/src/test/rustdoc-json/reexport/in_root_and_mod.rs
+++ b/src/test/rustdoc-json/reexport/in_root_and_mod.rs
@@ -1,8 +1,7 @@
 #![feature(no_core)]
 #![no_core]
 
-// @is "$.index[*][?(@.name=='foo')].kind" \"module\"
-// @is "$.index[*][?(@.name=='foo')].inner.is_stripped" "true"
+// @!has "$.index[*][?(@.name=='foo')]"
 mod foo {
     // @has "$.index[*][?(@.name=='Foo')]"
     pub struct Foo;
diff --git a/src/test/rustdoc-json/reexport/mod_not_included.rs b/src/test/rustdoc-json/reexport/mod_not_included.rs
new file mode 100644
index 00000000000..7b7600ef20f
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/mod_not_included.rs
@@ -0,0 +1,14 @@
+// Regression test for https://github.com/rust-lang/rust/issues/101103
+
+#![feature(no_core)]
+#![no_core]
+
+mod m1 {
+    pub fn x() {}
+}
+
+pub use m1::x;
+
+// @has "$.index[*][?(@.name=='x' && @.kind=='function')]"
+// @has "$.index[*][?(@.kind=='import' && @.inner.name=='x')].inner.source" '"m1::x"'
+// @!has "$.index[*][?(@.name=='m1')]"
diff --git a/src/test/rustdoc-json/reexport/private_two_names.rs b/src/test/rustdoc-json/reexport/private_two_names.rs
index ec78b06d09a..9858538a9d0 100644
--- a/src/test/rustdoc-json/reexport/private_two_names.rs
+++ b/src/test/rustdoc-json/reexport/private_two_names.rs
@@ -6,8 +6,7 @@
 #![no_core]
 #![feature(no_core)]
 
-// @is "$.index[*][?(@.name=='style')].kind" \"module\"
-// @is "$.index[*][?(@.name=='style')].inner.is_stripped" "true"
+// @!has "$.index[*][?(@.name=='style')]"
 mod style {
     // @set color_struct_id = "$.index[*][?(@.kind=='struct' && @.name=='Color')].id"
     pub struct Color;
diff --git a/src/test/rustdoc-json/reexport/rename_private.rs b/src/test/rustdoc-json/reexport/rename_private.rs
index 1537f834481..8fd850f9b13 100644
--- a/src/test/rustdoc-json/reexport/rename_private.rs
+++ b/src/test/rustdoc-json/reexport/rename_private.rs
@@ -3,8 +3,7 @@
 #![no_core]
 #![feature(no_core)]
 
-// @is "$.index[*][?(@.name=='inner')].kind" \"module\"
-// @is "$.index[*][?(@.name=='inner')].inner.is_stripped" "true"
+// @!has "$.index[*][?(@.kind=='inner')]"
 mod inner {
     // @has "$.index[*][?(@.name=='Public')]"
     pub struct Public;
diff --git a/src/test/rustdoc-json/reexport/simple_private.rs b/src/test/rustdoc-json/reexport/simple_private.rs
index 82348b383c3..d058ce0598d 100644
--- a/src/test/rustdoc-json/reexport/simple_private.rs
+++ b/src/test/rustdoc-json/reexport/simple_private.rs
@@ -2,16 +2,15 @@
 #![no_core]
 #![feature(no_core)]
 
-// @is "$.index[*][?(@.name=='inner')].kind" \"module\"
-// @is "$.index[*][?(@.name=='inner')].inner.is_stripped" "true"
+// @!has "$.index[*][?(@.name=='inner')]"
 mod inner {
     // @set pub_id = "$.index[*][?(@.name=='Public')].id"
     pub struct Public;
 }
 
 // @is "$.index[*][?(@.kind=='import')].inner.name" \"Public\"
+// @is "$.index[*][?(@.kind=='import')].inner.id" $pub_id
 // @set use_id = "$.index[*][?(@.kind=='import')].id"
 pub use inner::Public;
 
-// @ismany "$.index[*][?(@.name=='inner')].inner.items[*]" $pub_id
 // @ismany "$.index[*][?(@.name=='simple_private')].inner.items[*]" $use_id
diff --git a/src/test/rustdoc-json/stripped_modules.rs b/src/test/rustdoc-json/stripped_modules.rs
index 33e95ce69d0..d2664b49e9c 100644
--- a/src/test/rustdoc-json/stripped_modules.rs
+++ b/src/test/rustdoc-json/stripped_modules.rs
@@ -12,7 +12,7 @@ mod pub_inner_unreachable {
     pub fn pub_inner_1() {}
 }
 
-// @has "$.index[*][?(@.name=='pub_inner_reachable')]"
+// @!has "$.index[*][?(@.name=='pub_inner_reachable')]"
 mod pub_inner_reachable {
     // @has "$.index[*][?(@.name=='pub_inner_2')]"
     pub fn pub_inner_2() {}
diff --git a/src/test/ui/consts/miri_unleashed/ptr_arith.rs b/src/test/ui/consts/miri_unleashed/ptr_arith.rs
index 13e6af36e02..6a19b294585 100644
--- a/src/test/ui/consts/miri_unleashed/ptr_arith.rs
+++ b/src/test/ui/consts/miri_unleashed/ptr_arith.rs
@@ -8,7 +8,7 @@
 static PTR_INT_CAST: () = {
     let x = &0 as *const _ as usize;
     //~^ ERROR could not evaluate static initializer
-    //~| "exposing pointers" needs an rfc before being allowed inside constants
+    //~| exposing pointers
     let _v = x == x;
 };
 
@@ -19,4 +19,7 @@ static PTR_INT_TRANSMUTE: () = unsafe {
     //~| unable to turn pointer into raw bytes
 };
 
+// I'd love to test pointer comparison, but that is not possible since
+// their `PartialEq` impl is non-`const`.
+
 fn main() {}
diff --git a/src/test/ui/consts/miri_unleashed/ptr_arith.stderr b/src/test/ui/consts/miri_unleashed/ptr_arith.stderr
index 00cff23fb3f..f5c5ee2b8eb 100644
--- a/src/test/ui/consts/miri_unleashed/ptr_arith.stderr
+++ b/src/test/ui/consts/miri_unleashed/ptr_arith.stderr
@@ -2,7 +2,7 @@ error[E0080]: could not evaluate static initializer
   --> $DIR/ptr_arith.rs:9:13
    |
 LL |     let x = &0 as *const _ as usize;
-   |             ^^^^^^^^^^^^^^^^^^^^^^^ "exposing pointers" needs an rfc before being allowed inside constants
+   |             ^^^^^^^^^^^^^^^^^^^^^^^ exposing pointers is not possible at compile-time
 
 error[E0080]: could not evaluate static initializer
   --> $DIR/ptr_arith.rs:17:14
diff --git a/src/test/ui/copy-a-resource.stderr b/src/test/ui/copy-a-resource.stderr
index b92449c6e0a..128087f1e37 100644
--- a/src/test/ui/copy-a-resource.stderr
+++ b/src/test/ui/copy-a-resource.stderr
@@ -10,10 +10,6 @@ LL |     let _y = x.clone();
    = help: items from traits can only be used if the trait is implemented and in scope
    = note: the following trait defines an item `clone`, perhaps you need to implement it:
            candidate #1: `Clone`
-help: one of the expressions' fields has a method of the same name
-   |
-LL |     let _y = x.i.clone();
-   |                ++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-2823.stderr b/src/test/ui/issues/issue-2823.stderr
index 208b340d064..b5a2b2f55a6 100644
--- a/src/test/ui/issues/issue-2823.stderr
+++ b/src/test/ui/issues/issue-2823.stderr
@@ -10,10 +10,6 @@ LL |     let _d = c.clone();
    = help: items from traits can only be used if the trait is implemented and in scope
    = note: the following trait defines an item `clone`, perhaps you need to implement it:
            candidate #1: `Clone`
-help: one of the expressions' fields has a method of the same name
-   |
-LL |     let _d = c.x.clone();
-   |                ++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/noncopyable-class.stderr b/src/test/ui/noncopyable-class.stderr
index 15e22e946da..0c696163a26 100644
--- a/src/test/ui/noncopyable-class.stderr
+++ b/src/test/ui/noncopyable-class.stderr
@@ -10,14 +10,6 @@ LL |     let _y = x.clone();
    = help: items from traits can only be used if the trait is implemented and in scope
    = note: the following trait defines an item `clone`, perhaps you need to implement it:
            candidate #1: `Clone`
-help: one of the expressions' fields has a method of the same name
-   |
-LL |     let _y = x.i.clone();
-   |                ++
-help: one of the expressions' fields has a method of the same name
-   |
-LL |     let _y = x.j.x.clone();
-   |                ++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/suggestions/too-many-field-suggestions.rs b/src/test/ui/suggestions/too-many-field-suggestions.rs
new file mode 100644
index 00000000000..905f9502cf5
--- /dev/null
+++ b/src/test/ui/suggestions/too-many-field-suggestions.rs
@@ -0,0 +1,29 @@
+struct Thing {
+    a0: Foo,
+    a1: Foo,
+    a2: Foo,
+    a3: Foo,
+    a4: Foo,
+    a5: Foo,
+    a6: Foo,
+    a7: Foo,
+    a8: Foo,
+    a9: Foo,
+}
+
+struct Foo {
+    field: Field,
+}
+
+struct Field;
+
+impl Foo {
+    fn bar(&self) {}
+}
+
+fn bar(t: Thing) {
+    t.bar(); //~ ERROR no method named `bar` found for struct `Thing`
+    t.field; //~ ERROR no field `field` on type `Thing`
+}
+
+fn main() {}
diff --git a/src/test/ui/suggestions/too-many-field-suggestions.stderr b/src/test/ui/suggestions/too-many-field-suggestions.stderr
new file mode 100644
index 00000000000..63ad6fdb169
--- /dev/null
+++ b/src/test/ui/suggestions/too-many-field-suggestions.stderr
@@ -0,0 +1,44 @@
+error[E0599]: no method named `bar` found for struct `Thing` in the current scope
+  --> $DIR/too-many-field-suggestions.rs:25:7
+   |
+LL | struct Thing {
+   | ------------ method `bar` not found for this struct
+...
+LL |     t.bar();
+   |       ^^^ method not found in `Thing`
+   |
+help: some of the expressions' fields have a method of the same name
+   |
+LL |     t.a0.bar();
+   |       +++
+LL |     t.a1.bar();
+   |       +++
+LL |     t.a2.bar();
+   |       +++
+LL |     t.a3.bar();
+   |       +++
+     and 6 other candidates
+
+error[E0609]: no field `field` on type `Thing`
+  --> $DIR/too-many-field-suggestions.rs:26:7
+   |
+LL |     t.field;
+   |       ^^^^^ unknown field
+   |
+   = note: available fields are: `a0`, `a1`, `a2`, `a3`, `a4` ... and 5 others
+help: some of the expressions' fields have a field of the same name
+   |
+LL |     t.a0.field;
+   |       +++
+LL |     t.a1.field;
+   |       +++
+LL |     t.a2.field;
+   |       +++
+LL |     t.a3.field;
+   |       +++
+     and 6 other candidates
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0599, E0609.
+For more information about an error, try `rustc --explain E0599`.