Auto merge of #153074 - jhpratt:rollup-6aKDmTD, r=jhpratt

Rollup of 12 pull requests

Successful merges:

 - rust-lang/rust#149169 (ptr::replace: make calls on ZST null ptr not UB)
 - rust-lang/rust#150562 (Fix doc link used in suggestion for pinning self)
 - rust-lang/rust#152418 (`BTreeMap::merge` optimized)
 - rust-lang/rust#152679 (rustc_expand: improve diagnostics for non-repeatable metavars)
 - rust-lang/rust#152952 (mGCA: improve ogca diagnostic message )
 - rust-lang/rust#152977 (Fix relative path handling for --extern-html-root-url)
 - rust-lang/rust#153017 (Implement debuginfo for unsafe binder types)
 - rust-lang/rust#152868 (delete some very old trivial `Box` tests)
 - rust-lang/rust#152922 (rustc_public: Make fields that shouldn't be exposed visible only in `rustc_public`)
 - rust-lang/rust#153032 (Fix attribute parser and kind names.)
 - rust-lang/rust#153051 (Migration of `LintDiagnostic` - part 3)
 - rust-lang/rust#153060 (Give a better error when updating a submodule fails)

Author: bors

rustc_public/src/ty.rs

@@ -862,17 +862,11 @@ pub struct Discr {
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, Serialize)]
 pub struct VariantDef {
     /// The variant index.
-    ///
-    /// ## Warning
-    /// Do not access this field directly!
-    pub idx: VariantIdx,
+    pub(crate) idx: VariantIdx,
     /// The data type where this variant comes from.
     /// For now, we use this to retrieve information about the variant itself so we don't need to
     /// cache more information.
-    ///
-    /// ## Warning
-    /// Do not access this field directly!
-    pub adt_def: AdtDef,
+    pub(crate) adt_def: AdtDef,
 }
 
 impl VariantDef {
@@ -894,10 +888,7 @@ impl VariantDef {
 #[derive(Clone, Debug, Eq, PartialEq, Serialize)]
 pub struct FieldDef {
     /// The field definition.
-    ///
-    /// ## Warning
-    /// Do not access this field directly! This is public for the compiler to have access to it.
-    pub def: DefId,
+    pub(crate) def: DefId,
 
     /// The field name.
     pub name: Symbol,