Auto merge of #139482 - Zalathar:rollup-h2ht1y6, r=Zalathar

Rollup of 9 pull requests

Successful merges:

 - #139035 (Add new `PatKind::Missing` variants)
 - #139108 (Simplify `thir::PatKind::ExpandedConstant`)
 - #139112 (Implement `super let`)
 - #139365 (Default auto traits: fix perf)
 - #139397 (coverage: Build the CGU's global file table as late as possible)
 - #139455 ( Remove support for `extern "rust-intrinsic"` blocks)
 - #139461 (Stop calling `source_span` query in significant drop order code)
 - #139465 (add sret handling for scalar autodiff)
 - #139466 (Trivial tweaks to stop tracking source span directly)

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

19 files changed, 23 insertions, 100 deletions

diff --git a/src/doc/unstable-book/src/language-features/intrinsics.md b/src/doc/unstable-book/src/language-features/intrinsics.md
index 975b400447e..a0e38f340f5 100644
--- a/src/doc/unstable-book/src/language-features/intrinsics.md
+++ b/src/doc/unstable-book/src/language-features/intrinsics.md
@@ -52,9 +52,8 @@ with any regular function.
 Various intrinsics have native MIR operations that they correspond to. Instead of requiring
 backends to implement both the intrinsic and the MIR operation, the `lower_intrinsics` pass
 will convert the calls to the MIR operation. Backends do not need to know about these intrinsics
-at all. These intrinsics only make sense without a body, and can either be declared as a "rust-intrinsic"
-or as a `#[rustc_intrinsic]`. The body is never used, as calls to the intrinsic do not exist
-anymore after MIR analyses.
+at all. These intrinsics only make sense without a body, and can be declared as a `#[rustc_intrinsic]`.
+The body is never used, as calls to the intrinsic do not exist anymore after MIR analyses.
 
 ## Intrinsics without fallback logic
 
@@ -70,28 +69,3 @@ These are written without a body:
 #[rustc_intrinsic]
 pub fn abort() -> !;
 ```
-
-### Legacy extern ABI based intrinsics
-
-*This style is deprecated, always prefer the above form.*
-
-These are imported as if they were FFI functions, with the special
-`rust-intrinsic` ABI. For example, if one was in a freestanding
-context, but wished to be able to `transmute` between types, and
-perform efficient pointer arithmetic, one would import those functions
-via a declaration like
-
-```rust
-#![feature(intrinsics)]
-#![allow(internal_features)]
-# fn main() {}
-
-extern "rust-intrinsic" {
-    fn transmute<T, U>(x: T) -> U;
-
-    fn arith_offset<T>(dst: *const T, offset: isize) -> *const T;
-}
-```
-
-As with any other FFI functions, these are by default always `unsafe` to call.
-You can add `#[rustc_safe_intrinsic]` to the intrinsic to make it safe to call.
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
index d3ddb77c0b3..06e75fe1764 100644
--- a/src/librustdoc/clean/types.rs
+++ b/src/librustdoc/clean/types.rs
@@ -11,7 +11,6 @@ use rustc_hir::def::{CtorKind, DefKind, Res};
 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE, LocalDefId};
 use rustc_hir::lang_items::LangItem;
 use rustc_hir::{BodyId, Mutability};
-use rustc_hir_analysis::check::intrinsic::intrinsic_operation_unsafety;
 use rustc_index::IndexVec;
 use rustc_metadata::rendered_const;
 use rustc_middle::span_bug;
@@ -687,8 +686,6 @@ impl Item {
                 hir::FnHeader {
                     safety: if tcx.codegen_fn_attrs(def_id).safe_target_features {
                         hir::HeaderSafety::SafeTargetFeatures
-                    } else if abi == ExternAbi::RustIntrinsic {
-                        intrinsic_operation_unsafety(tcx, def_id.expect_local()).into()
                     } else {
                         safety.into()
                     },
diff --git a/src/librustdoc/clean/utils.rs b/src/librustdoc/clean/utils.rs
index f81db58950c..afcca81a485 100644
--- a/src/librustdoc/clean/utils.rs
+++ b/src/librustdoc/clean/utils.rs
@@ -304,6 +304,7 @@ pub(crate) fn name_from_pat(p: &hir::Pat<'_>) -> Symbol {
 
     Symbol::intern(&match &p.kind {
         // FIXME(never_patterns): does this make sense?
+        PatKind::Missing => unreachable!(),
         PatKind::Wild
         | PatKind::Err(_)
         | PatKind::Never
diff --git a/src/tools/clippy/clippy_lints/src/equatable_if_let.rs b/src/tools/clippy/clippy_lints/src/equatable_if_let.rs
index cd9ab2764ac..3afb687040f 100644
--- a/src/tools/clippy/clippy_lints/src/equatable_if_let.rs
+++ b/src/tools/clippy/clippy_lints/src/equatable_if_let.rs
@@ -45,6 +45,7 @@ fn unary_pattern(pat: &Pat<'_>) -> bool {
         pats.iter().all(unary_pattern)
     }
     match &pat.kind {
+        PatKind::Missing => unreachable!(),
         PatKind::Slice(_, _, _)
         | PatKind::Range(_, _, _)
         | PatKind::Binding(..)
diff --git a/src/tools/clippy/clippy_lints/src/matches/match_same_arms.rs b/src/tools/clippy/clippy_lints/src/matches/match_same_arms.rs
index 250f17fa902..a21597ffb93 100644
--- a/src/tools/clippy/clippy_lints/src/matches/match_same_arms.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/match_same_arms.rs
@@ -253,6 +253,7 @@ fn iter_matching_struct_fields<'a>(
 impl<'a> NormalizedPat<'a> {
     fn from_pat(cx: &LateContext<'_>, arena: &'a DroplessArena, pat: &'a Pat<'_>) -> Self {
         match pat.kind {
+            PatKind::Missing => unreachable!(),
             PatKind::Wild | PatKind::Binding(.., None) => Self::Wild,
             PatKind::Binding(.., Some(pat))
             | PatKind::Box(pat)
diff --git a/src/tools/clippy/clippy_lints/src/matches/single_match.rs b/src/tools/clippy/clippy_lints/src/matches/single_match.rs
index 56fbd626eef..836c46240ce 100644
--- a/src/tools/clippy/clippy_lints/src/matches/single_match.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/single_match.rs
@@ -406,6 +406,7 @@ impl<'a> PatState<'a> {
                 pats.iter().map(|p| p.pat),
             ),
 
+            PatKind::Missing => unreachable!(),
             PatKind::Wild
             | PatKind::Binding(_, _, _, None)
             | PatKind::Expr(_)
diff --git a/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs b/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
index f43715d6752..8966e6851ac 100644
--- a/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
+++ b/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
@@ -224,6 +224,7 @@ fn transform_with_focus_on_idx(alternatives: &mut ThinVec<P<Pat>>, focus_idx: us
 
     // We're trying to find whatever kind (~"constructor") we found in `alternatives[start..]`.
     let changed = match &mut focus_kind {
+        Missing => unreachable!(),
         // These pattern forms are "leafs" and do not have sub-patterns.
         // Therefore they are not some form of constructor `C`,
         // with which a pattern `C(p_0)` may be formed,
diff --git a/src/tools/clippy/clippy_lints/src/utils/author.rs b/src/tools/clippy/clippy_lints/src/utils/author.rs
index 4309cd2c9ab..b7dcd2ffb0e 100644
--- a/src/tools/clippy/clippy_lints/src/utils/author.rs
+++ b/src/tools/clippy/clippy_lints/src/utils/author.rs
@@ -676,6 +676,7 @@ impl<'a, 'tcx> PrintVisitor<'a, 'tcx> {
         }
 
         match pat.value.kind {
+            PatKind::Missing => unreachable!(),
             PatKind::Wild => kind!("Wild"),
             PatKind::Never => kind!("Never"),
             PatKind::Binding(ann, _, name, sub) => {
diff --git a/src/tools/clippy/clippy_utils/src/ast_utils/mod.rs b/src/tools/clippy/clippy_utils/src/ast_utils/mod.rs
index eba576392eb..c5dce26143b 100644
--- a/src/tools/clippy/clippy_utils/src/ast_utils/mod.rs
+++ b/src/tools/clippy/clippy_utils/src/ast_utils/mod.rs
@@ -33,6 +33,7 @@ pub fn eq_id(l: Ident, r: Ident) -> bool {
 pub fn eq_pat(l: &Pat, r: &Pat) -> bool {
     use PatKind::*;
     match (&l.kind, &r.kind) {
+        (Missing, _) | (_, Missing) => unreachable!(),
         (Paren(l), _) => eq_pat(l, r),
         (_, Paren(r)) => eq_pat(l, r),
         (Wild, Wild) | (Rest, Rest) => true,
diff --git a/src/tools/clippy/clippy_utils/src/hir_utils.rs b/src/tools/clippy/clippy_utils/src/hir_utils.rs
index 9938e64d242..b813cd361ed 100644
--- a/src/tools/clippy/clippy_utils/src/hir_utils.rs
+++ b/src/tools/clippy/clippy_utils/src/hir_utils.rs
@@ -1124,6 +1124,7 @@ impl<'a, 'tcx> SpanlessHash<'a, 'tcx> {
     pub fn hash_pat(&mut self, pat: &Pat<'_>) {
         std::mem::discriminant(&pat.kind).hash(&mut self.s);
         match pat.kind {
+            PatKind::Missing => unreachable!(),
             PatKind::Binding(BindingMode(by_ref, mutability), _, _, pat) => {
                 std::mem::discriminant(&by_ref).hash(&mut self.s);
                 std::mem::discriminant(&mutability).hash(&mut self.s);
diff --git a/src/tools/clippy/clippy_utils/src/lib.rs b/src/tools/clippy/clippy_utils/src/lib.rs
index 6d2c2a2d692..bcb0f8349e2 100644
--- a/src/tools/clippy/clippy_utils/src/lib.rs
+++ b/src/tools/clippy/clippy_utils/src/lib.rs
@@ -1858,6 +1858,7 @@ pub fn is_refutable(cx: &LateContext<'_>, pat: &Pat<'_>) -> bool {
     }
 
     match pat.kind {
+        PatKind::Missing => unreachable!(),
         PatKind::Wild | PatKind::Never => false, // If `!` typechecked then the type is empty, so not refutable.
         PatKind::Binding(_, _, _, pat) => pat.is_some_and(|pat| is_refutable(cx, pat)),
         PatKind::Box(pat) | PatKind::Ref(pat, _) => is_refutable(cx, pat),
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/lib.rs b/src/tools/rust-analyzer/crates/hir-ty/src/lib.rs
index cc02b71f05c..e4c50f2ebdb 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/lib.rs
@@ -400,7 +400,6 @@ pub enum FnAbi {
     Rust,
     RustCall,
     RustCold,
-    RustIntrinsic,
     Stdcall,
     StdcallUnwind,
     System,
@@ -457,7 +456,6 @@ impl FnAbi {
             s if *s == sym::riscv_dash_interrupt_dash_s => FnAbi::RiscvInterruptS,
             s if *s == sym::rust_dash_call => FnAbi::RustCall,
             s if *s == sym::rust_dash_cold => FnAbi::RustCold,
-            s if *s == sym::rust_dash_intrinsic => FnAbi::RustIntrinsic,
             s if *s == sym::Rust => FnAbi::Rust,
             s if *s == sym::stdcall_dash_unwind => FnAbi::StdcallUnwind,
             s if *s == sym::stdcall => FnAbi::Stdcall,
@@ -500,7 +498,6 @@ impl FnAbi {
             FnAbi::Rust => "Rust",
             FnAbi::RustCall => "rust-call",
             FnAbi::RustCold => "rust-cold",
-            FnAbi::RustIntrinsic => "rust-intrinsic",
             FnAbi::Stdcall => "stdcall",
             FnAbi::StdcallUnwind => "stdcall-unwind",
             FnAbi::System => "system",
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/mir/eval/shim.rs b/src/tools/rust-analyzer/crates/hir-ty/src/mir/eval/shim.rs
index f61ecabb7e4..06ac5b1ffad 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/mir/eval/shim.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/mir/eval/shim.rs
@@ -59,19 +59,7 @@ impl Evaluator<'_> {
 
         let function_data = self.db.function_data(def);
         let attrs = self.db.attrs(def.into());
-        let is_intrinsic = attrs.by_key(&sym::rustc_intrinsic).exists()
-            // Keep this around for a bit until extern "rustc-intrinsic" abis are no longer used
-            || (match &function_data.abi {
-                Some(abi) => *abi == sym::rust_dash_intrinsic,
-                None => match def.lookup(self.db.upcast()).container {
-                    hir_def::ItemContainerId::ExternBlockId(block) => {
-                        let id = block.lookup(self.db.upcast()).id;
-                        id.item_tree(self.db.upcast())[id.value].abi.as_ref()
-                            == Some(&sym::rust_dash_intrinsic)
-                    }
-                    _ => false,
-                },
-            });
+        let is_intrinsic = attrs.by_key(&sym::rustc_intrinsic).exists();
 
         if is_intrinsic {
             return self.exec_intrinsic(
diff --git a/src/tools/rust-analyzer/crates/hir-ty/src/utils.rs b/src/tools/rust-analyzer/crates/hir-ty/src/utils.rs
index 89d89fe2230..0cfd36d9166 100644
--- a/src/tools/rust-analyzer/crates/hir-ty/src/utils.rs
+++ b/src/tools/rust-analyzer/crates/hir-ty/src/utils.rs
@@ -18,7 +18,6 @@ use hir_def::{
     TypeOrConstParamId,
 };
 use hir_expand::name::Name;
-use intern::sym;
 use rustc_abi::TargetDataLayout;
 use rustc_hash::FxHashSet;
 use smallvec::{smallvec, SmallVec};
@@ -303,26 +302,13 @@ pub fn is_fn_unsafe_to_call(
 
     let loc = func.lookup(db.upcast());
     match loc.container {
-        hir_def::ItemContainerId::ExternBlockId(block) => {
-            let id = block.lookup(db.upcast()).id;
-            let is_intrinsic_block =
-                id.item_tree(db.upcast())[id.value].abi.as_ref() == Some(&sym::rust_dash_intrinsic);
-            if is_intrinsic_block {
-                // legacy intrinsics
-                // extern "rust-intrinsic" intrinsics are unsafe unless they have the rustc_safe_intrinsic attribute
-                if db.attrs(func.into()).by_key(&sym::rustc_safe_intrinsic).exists() {
-                    Unsafety::Safe
-                } else {
-                    Unsafety::Unsafe
-                }
+        hir_def::ItemContainerId::ExternBlockId(_block) => {
+            // Function in an `extern` block are always unsafe to call, except when
+            // it is marked as `safe`.
+            if data.is_safe() {
+                Unsafety::Safe
             } else {
-                // Function in an `extern` block are always unsafe to call, except when
-                // it is marked as `safe`.
-                if data.is_safe() {
-                    Unsafety::Safe
-                } else {
-                    Unsafety::Unsafe
-                }
+                Unsafety::Unsafe
             }
         }
         _ => Unsafety::Safe,
diff --git a/src/tools/rust-analyzer/crates/ide-completion/src/completions/extern_abi.rs b/src/tools/rust-analyzer/crates/ide-completion/src/completions/extern_abi.rs
index 7c2cc2a6c1d..a3554114f4c 100644
--- a/src/tools/rust-analyzer/crates/ide-completion/src/completions/extern_abi.rs
+++ b/src/tools/rust-analyzer/crates/ide-completion/src/completions/extern_abi.rs
@@ -36,7 +36,6 @@ const SUPPORTED_CALLING_CONVENTIONS: &[&str] = &[
     "wasm",
     "system",
     "system-unwind",
-    "rust-intrinsic",
     "rust-call",
     "unadjusted",
 ];
diff --git a/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs b/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
index 6b470d921f7..5dfd826d7f9 100644
--- a/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
@@ -6945,9 +6945,8 @@ fn hover_feature() {
             Various intrinsics have native MIR operations that they correspond to. Instead of requiring
             backends to implement both the intrinsic and the MIR operation, the `lower_intrinsics` pass
             will convert the calls to the MIR operation. Backends do not need to know about these intrinsics
-            at all. These intrinsics only make sense without a body, and can either be declared as a "rust-intrinsic"
-            or as a `#[rustc_intrinsic]`. The body is never used, as calls to the intrinsic do not exist
-            anymore after MIR analyses.
+            at all. These intrinsics only make sense without a body, and can be as a `#[rustc_intrinsic]`. 
+            The body is never used, as calls to the intrinsic do not exist anymore after MIR analyses.
 
             ## Intrinsics without fallback logic
 
@@ -6960,29 +6959,6 @@ fn hover_feature() {
             `#[rustc_intrinsic_must_be_overridden]` to the function to ensure that backends don't
             invoke the body.
 
-            ### Legacy extern ABI based intrinsics
-
-            These are imported as if they were FFI functions, with the special
-            `rust-intrinsic` ABI. For example, if one was in a freestanding
-            context, but wished to be able to `transmute` between types, and
-            perform efficient pointer arithmetic, one would import those functions
-            via a declaration like
-
-            ```rust
-            #![feature(intrinsics)]
-            #![allow(internal_features)]
-            # fn main() {}
-
-            extern "rust-intrinsic" {
-                fn transmute<T, U>(x: T) -> U;
-
-                fn arith_offset<T>(dst: *const T, offset: isize) -> *const T;
-            }
-            ```
-
-            As with any other FFI functions, these are by default always `unsafe` to call.
-            You can add `#[rustc_safe_intrinsic]` to the intrinsic to make it safe to call.
-
         "#]],
     )
 }
diff --git a/src/tools/rust-analyzer/crates/intern/src/symbol/symbols.rs b/src/tools/rust-analyzer/crates/intern/src/symbol/symbols.rs
index 6b77c72cee8..d4f334289f0 100644
--- a/src/tools/rust-analyzer/crates/intern/src/symbol/symbols.rs
+++ b/src/tools/rust-analyzer/crates/intern/src/symbol/symbols.rs
@@ -125,7 +125,6 @@ define_symbols! {
     riscv_dash_interrupt_dash_s = "riscv-interrupt-s",
     rust_dash_call = "rust-call",
     rust_dash_cold = "rust-cold",
-    rust_dash_intrinsic = "rust-intrinsic",
     stdcall_dash_unwind = "stdcall-unwind",
     system_dash_unwind = "system-unwind",
     sysv64_dash_unwind = "sysv64-unwind",
diff --git a/src/tools/rustfmt/src/items.rs b/src/tools/rustfmt/src/items.rs
index 322af97d9dc..5c3be769f9e 100644
--- a/src/tools/rustfmt/src/items.rs
+++ b/src/tools/rustfmt/src/items.rs
@@ -2442,11 +2442,7 @@ pub(crate) fn span_hi_for_param(context: &RewriteContext<'_>, param: &ast::Param
 }
 
 pub(crate) fn is_named_param(param: &ast::Param) -> bool {
-    if let ast::PatKind::Ident(_, ident, _) = param.pat.kind {
-        ident.name != symbol::kw::Empty
-    } else {
-        true
-    }
+    !matches!(param.pat.kind, ast::PatKind::Missing)
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
diff --git a/src/tools/rustfmt/src/patterns.rs b/src/tools/rustfmt/src/patterns.rs
index 8dc94574503..cb3879f4be8 100644
--- a/src/tools/rustfmt/src/patterns.rs
+++ b/src/tools/rustfmt/src/patterns.rs
@@ -42,6 +42,7 @@ pub(crate) fn is_short_pattern(
 
 fn is_short_pattern_inner(context: &RewriteContext<'_>, pat: &ast::Pat) -> bool {
     match &pat.kind {
+        ast::PatKind::Missing => unreachable!(),
         ast::PatKind::Rest | ast::PatKind::Never | ast::PatKind::Wild | ast::PatKind::Err(_) => {
             true
         }
@@ -100,6 +101,7 @@ impl Rewrite for Pat {
 
     fn rewrite_result(&self, context: &RewriteContext<'_>, shape: Shape) -> RewriteResult {
         match self.kind {
+            PatKind::Missing => unreachable!(),
             PatKind::Or(ref pats) => {
                 let pat_strs = pats
                     .iter()