Rollup merge of #104383 - WaffleLapkin:rustc_undiagnostic_item, r=compiler-errors

Remove unused symbols and diagnostic items

As the title suggests, this removes unused symbols from `sym::` and `#[rustc_diagnostic_item]` annotations that weren't mentioned anywhere.

Originally I tried to use grep, to find symbols and item names that are never mentioned via `sym::name`, however this produced a lot of false positives (?), for example clippy matching on `Symbol::as_str` or macros "implicitly" adding `sym::`. I ended up fixing all these false positives (?) by hand, but tbh I'm not sure if it was worth it...

7 files changed, 7 insertions, 79 deletions

diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs
index c35bb0cc475..bad6d587907 100644
--- a/compiler/rustc_span/src/symbol.rs
+++ b/compiler/rustc_span/src/symbol.rs
@@ -170,8 +170,6 @@ symbols! {
         Count,
         Cow,
         Debug,
-        DebugStruct,
-        DebugTuple,
         Decodable,
         Decoder,
         DecorateLint,
@@ -190,9 +188,6 @@ symbols! {
         Error,
         File,
         FileType,
-        Fn,
-        FnMut,
-        FnOnce,
         FormatSpec,
         Formatter,
         From,
@@ -211,7 +206,6 @@ symbols! {
         Input,
         Into,
         IntoDiagnostic,
-        IntoFuture,
         IntoIterator,
         IoRead,
         IoWrite,
@@ -256,7 +250,6 @@ symbols! {
         Pointer,
         Poll,
         ProcMacro,
-        ProcMacroHack,
         ProceduralMasqueradeDummyType,
         Range,
         RangeFrom,
@@ -332,7 +325,6 @@ symbols! {
         abi_vectorcall,
         abi_x86_interrupt,
         abort,
-        aborts,
         add,
         add_assign,
         add_with_overflow,
@@ -344,7 +336,6 @@ symbols! {
         align,
         align_offset,
         alignment,
-        alignstack,
         all,
         alloc,
         alloc_error_handler,
@@ -433,7 +424,6 @@ symbols! {
         bool,
         borrowck_graphviz_format,
         borrowck_graphviz_postflow,
-        borrowck_graphviz_preflow,
         box_free,
         box_patterns,
         box_syntax,
@@ -462,7 +452,6 @@ symbols! {
         cfg_doctest,
         cfg_eval,
         cfg_hide,
-        cfg_macro,
         cfg_panic,
         cfg_sanitize,
         cfg_target_abi,
@@ -470,7 +459,6 @@ symbols! {
         cfg_target_feature,
         cfg_target_has_atomic,
         cfg_target_has_atomic_equal_alignment,
-        cfg_target_has_atomic_load_store,
         cfg_target_thread_local,
         cfg_target_vendor,
         cfg_version,
@@ -495,19 +483,15 @@ symbols! {
         cold,
         collapse_debuginfo,
         column,
-        column_macro,
-        compare_and_swap,
         compare_exchange,
         compare_exchange_weak,
         compile_error,
-        compile_error_macro,
         compiler,
         compiler_builtins,
         compiler_fence,
         concat,
         concat_bytes,
         concat_idents,
-        concat_macro,
         conservative_impl_trait,
         console,
         const_allocate,
@@ -528,7 +512,6 @@ symbols! {
         const_fn_unsize,
         const_for,
         const_format_args,
-        const_generic_defaults,
         const_generics,
         const_generics_defaults,
         const_if_match,
@@ -547,22 +530,19 @@ symbols! {
         const_trait,
         const_trait_bound_opt_out,
         const_trait_impl,
-        const_transmute,
         const_try,
         constant,
         constructor,
-        contents,
         context,
-        convert,
         copy,
         copy_closures,
         copy_nonoverlapping,
         copysignf32,
         copysignf64,
         core,
-        core_intrinsics,
         core_panic,
         core_panic_2015_macro,
+        core_panic_2021_macro,
         core_panic_macro,
         cosf32,
         cosf64,
@@ -598,7 +578,6 @@ symbols! {
         debug_assertions,
         debug_struct,
         debug_struct_fields_finish,
-        debug_trait_builder,
         debug_tuple,
         debug_tuple_fields_finish,
         debugger_visualizer,
@@ -630,7 +609,6 @@ symbols! {
         discriminant_type,
         discriminant_value,
         dispatch_from_dyn,
-        display_trait,
         div,
         div_assign,
         doc,
@@ -661,7 +639,6 @@ symbols! {
         dyn_star,
         dyn_trait,
         e,
-        edition_macro_pats,
         edition_panic,
         eh_catch_typeinfo,
         eh_personality,
@@ -674,7 +651,6 @@ symbols! {
         encode,
         end,
         env,
-        env_macro,
         eprint_macro,
         eprintln_macro,
         eq,
@@ -724,9 +700,7 @@ symbols! {
         field,
         field_init_shorthand,
         file,
-        file_macro,
         fill,
-        finish,
         flags,
         float,
         float_to_int_unchecked,
@@ -735,8 +709,6 @@ symbols! {
         fmaf32,
         fmaf64,
         fmt,
-        fmt_as_str,
-        fmt_internals,
         fmul_fast,
         fn_align,
         fn_must_use,
@@ -751,7 +723,6 @@ symbols! {
         format_args_macro,
         format_args_nl,
         format_macro,
-        fp,
         freeze,
         freg,
         frem_fast,
@@ -814,7 +785,6 @@ symbols! {
         ignore,
         impl_header_lifetime_elision,
         impl_lint_pass,
-        impl_macros,
         impl_trait_in_bindings,
         impl_trait_in_fn_trait_return,
         implied_by,
@@ -826,7 +796,6 @@ symbols! {
         include,
         include_bytes,
         include_bytes_macro,
-        include_macro,
         include_str,
         include_str_macro,
         inclusive_range_syntax,
@@ -844,7 +813,6 @@ symbols! {
         instruction_set,
         integer_: "integer",
         integral,
-        intel,
         into_future,
         into_iter,
         intra_doc_pointers,
@@ -881,7 +849,6 @@ symbols! {
         lifetimes,
         likely,
         line,
-        line_macro,
         link,
         link_args,
         link_cfg,
@@ -926,7 +893,6 @@ symbols! {
         masked,
         match_beginning_vert,
         match_default_bindings,
-        matches_macro,
         maxnumf32,
         maxnumf64,
         may_dangle,
@@ -965,7 +931,6 @@ symbols! {
         modifiers,
         module,
         module_path,
-        module_path_macro,
         more_qualified_paths,
         more_struct_aliases,
         movbe_target_feature,
@@ -1059,7 +1024,6 @@ symbols! {
         optin_builtin_traits,
         option,
         option_env,
-        option_env_macro,
         options,
         or,
         or_patterns,
@@ -1102,7 +1066,6 @@ symbols! {
         plugins,
         pointee_trait,
         pointer,
-        pointer_trait_fmt,
         poll,
         position,
         post_dash_lto: "post-lto",
@@ -1129,7 +1092,6 @@ symbols! {
         proc_dash_macro: "proc-macro",
         proc_macro,
         proc_macro_attribute,
-        proc_macro_def_site,
         proc_macro_derive,
         proc_macro_expr,
         proc_macro_gen,
@@ -1230,9 +1192,6 @@ symbols! {
         rust_cold_cc,
         rust_eh_catch_typeinfo,
         rust_eh_personality,
-        rust_eh_register_frames,
-        rust_eh_unregister_frames,
-        rust_oom,
         rustc,
         rustc_allocator,
         rustc_allocator_zeroed,
@@ -1305,7 +1264,6 @@ symbols! {
         rustc_serialize,
         rustc_skip_array_during_method_dispatch,
         rustc_specialization_trait,
-        rustc_stable,
         rustc_std_internal_symbol,
         rustc_strict_coherence,
         rustc_symbol_name,
@@ -1433,7 +1391,6 @@ symbols! {
         static_recursion,
         staticlib,
         std,
-        std_inject,
         std_panic,
         std_panic_2015_macro,
         std_panic_macro,
@@ -1448,7 +1405,6 @@ symbols! {
         str_trim_start,
         strict_provenance,
         stringify,
-        stringify_macro,
         struct_field_attributes,
         struct_inherit,
         struct_variant,
@@ -1476,10 +1432,8 @@ symbols! {
         target_has_atomic_load_store,
         target_os,
         target_pointer_width,
-        target_target_vendor,
         target_thread_local,
         target_vendor,
-        task,
         tbm_target_feature,
         termination,
         termination_trait,
@@ -1491,7 +1445,6 @@ symbols! {
         test_removed_feature,
         test_runner,
         test_unstable_lint,
-        then_with,
         thread,
         thread_local,
         thread_local_macro,
@@ -1523,7 +1476,6 @@ symbols! {
         try_trait_v2,
         tt,
         tuple,
-        tuple_from_req,
         tuple_indexing,
         tuple_trait,
         two_phase,
@@ -1567,7 +1519,6 @@ symbols! {
         unreachable_2015,
         unreachable_2015_macro,
         unreachable_2021,
-        unreachable_2021_macro,
         unreachable_code,
         unreachable_display,
         unreachable_macro,
@@ -1586,7 +1537,6 @@ symbols! {
                           from crates.io via `Cargo.toml` instead?",
         untagged_unions,
         unused_imports,
-        unused_qualifications,
         unwind,
         unwind_attributes,
         unwind_safe_trait,
diff --git a/library/core/src/fmt/mod.rs b/library/core/src/fmt/mod.rs
index c8d28550567..2adc968bd46 100644
--- a/library/core/src/fmt/mod.rs
+++ b/library/core/src/fmt/mod.rs
@@ -1054,7 +1054,6 @@ pub trait UpperHex {
 pub trait Pointer {
     /// Formats the value using the given formatter.
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_diagnostic_item = "pointer_trait_fmt"]
     fn fmt(&self, f: &mut Formatter<'_>) -> Result;
 }
 
diff --git a/library/core/src/macros/mod.rs b/library/core/src/macros/mod.rs
index 32bdc26bc51..34247c05845 100644
--- a/library/core/src/macros/mod.rs
+++ b/library/core/src/macros/mod.rs
@@ -338,7 +338,6 @@ pub macro debug_assert_matches($($arg:tt)*) {
 /// ```
 #[macro_export]
 #[stable(feature = "matches_macro", since = "1.42.0")]
-#[cfg_attr(not(test), rustc_diagnostic_item = "matches_macro")]
 macro_rules! matches {
     ($expression:expr, $(|)? $( $pattern:pat_param )|+ $( if $guard: expr )? $(,)?) => {
         match $expression {
@@ -820,7 +819,6 @@ pub(crate) mod builtin {
     #[stable(feature = "compile_error_macro", since = "1.20.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "compile_error_macro")]
     macro_rules! compile_error {
         ($msg:expr $(,)?) => {{ /* compiler built-in */ }};
     }
@@ -944,7 +942,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "env_macro")]
     macro_rules! env {
         ($name:expr $(,)?) => {{ /* compiler built-in */ }};
         ($name:expr, $error_msg:expr $(,)?) => {{ /* compiler built-in */ }};
@@ -973,7 +970,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "option_env_macro")]
     macro_rules! option_env {
         ($name:expr $(,)?) => {{ /* compiler built-in */ }};
     }
@@ -1058,7 +1054,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "concat_macro")]
     macro_rules! concat {
         ($($e:expr),* $(,)?) => {{ /* compiler built-in */ }};
     }
@@ -1084,7 +1079,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "line_macro")]
     macro_rules! line {
         () => {
             /* compiler built-in */
@@ -1124,7 +1118,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "column_macro")]
     macro_rules! column {
         () => {
             /* compiler built-in */
@@ -1150,7 +1143,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "file_macro")]
     macro_rules! file {
         () => {
             /* compiler built-in */
@@ -1175,7 +1167,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "stringify_macro")]
     macro_rules! stringify {
         ($($t:tt)*) => {
             /* compiler built-in */
@@ -1282,7 +1273,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "module_path_macro")]
     macro_rules! module_path {
         () => {
             /* compiler built-in */
@@ -1316,7 +1306,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "cfg_macro")]
     macro_rules! cfg {
         ($($cfg:tt)*) => {
             /* compiler built-in */
@@ -1367,7 +1356,6 @@ pub(crate) mod builtin {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_builtin_macro]
     #[macro_export]
-    #[cfg_attr(not(test), rustc_diagnostic_item = "include_macro")]
     macro_rules! include {
         ($file:expr $(,)?) => {{ /* compiler built-in */ }};
     }
diff --git a/library/core/src/ops/function.rs b/library/core/src/ops/function.rs
index 910a92ec0d9..127b047db91 100644
--- a/library/core/src/ops/function.rs
+++ b/library/core/src/ops/function.rs
@@ -57,7 +57,6 @@ use crate::marker::Tuple;
 #[cfg(bootstrap)]
 #[lang = "fn"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "Fn"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
@@ -138,7 +137,6 @@ pub trait Fn<Args>: FnMut<Args> {
 #[cfg(not(bootstrap))]
 #[lang = "fn"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "Fn"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
@@ -227,7 +225,6 @@ pub trait Fn<Args: Tuple>: FnMut<Args> {
 #[cfg(bootstrap)]
 #[lang = "fn_mut"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "FnMut"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
@@ -316,7 +313,6 @@ pub trait FnMut<Args>: FnOnce<Args> {
 #[cfg(not(bootstrap))]
 #[lang = "fn_mut"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "FnMut"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
@@ -397,7 +393,6 @@ pub trait FnMut<Args: Tuple>: FnOnce<Args> {
 #[cfg(bootstrap)]
 #[lang = "fn_once"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "FnOnce"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
@@ -483,7 +478,6 @@ pub trait FnOnce<Args> {
 #[cfg(not(bootstrap))]
 #[lang = "fn_once"]
 #[stable(feature = "rust1", since = "1.0.0")]
-#[rustc_diagnostic_item = "FnOnce"]
 #[rustc_paren_sugar]
 #[rustc_on_unimplemented(
     on(
diff --git a/library/core/src/panic.rs b/library/core/src/panic.rs
index 00b63dfbd06..461b70c32f3 100644
--- a/library/core/src/panic.rs
+++ b/library/core/src/panic.rs
@@ -80,7 +80,6 @@ pub macro unreachable_2015 {
 #[doc(hidden)]
 #[unstable(feature = "edition_panic", issue = "none", reason = "use unreachable!() instead")]
 #[allow_internal_unstable(core_panic)]
-#[rustc_diagnostic_item = "unreachable_2021_macro"]
 #[rustc_macro_transparency = "semitransparent"]
 pub macro unreachable_2021 {
     () => (
diff --git a/library/std/src/net/ip_addr.rs b/library/std/src/net/ip_addr.rs
index 4f14fc28038..5453853e138 100644
--- a/library/std/src/net/ip_addr.rs
+++ b/library/std/src/net/ip_addr.rs
@@ -73,7 +73,6 @@ pub enum IpAddr {
 /// assert!("0xcb.0x0.0x71.0x00".parse::<Ipv4Addr>().is_err()); // all octets are in hex
 /// ```
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
-#[cfg_attr(not(test), rustc_diagnostic_item = "Ipv4Addr")]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Ipv4Addr {
     octets: [u8; 4],
@@ -156,7 +155,6 @@ pub struct Ipv4Addr {
 /// assert_eq!(localhost.is_loopback(), true);
 /// ```
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
-#[cfg_attr(not(test), rustc_diagnostic_item = "Ipv6Addr")]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Ipv6Addr {
     octets: [u8; 16],
diff --git a/src/tools/clippy/clippy_utils/src/macros.rs b/src/tools/clippy/clippy_utils/src/macros.rs
index 9a682fbe604..d13b34a66cc 100644
--- a/src/tools/clippy/clippy_utils/src/macros.rs
+++ b/src/tools/clippy/clippy_utils/src/macros.rs
@@ -199,12 +199,12 @@ pub fn first_node_in_macro(cx: &LateContext<'_>, node: &impl HirNode) -> Option<
 pub fn is_panic(cx: &LateContext<'_>, def_id: DefId) -> bool {
     let Some(name) = cx.tcx.get_diagnostic_name(def_id) else { return false };
     matches!(
-        name.as_str(),
-        "core_panic_macro"
-            | "std_panic_macro"
-            | "core_panic_2015_macro"
-            | "std_panic_2015_macro"
-            | "core_panic_2021_macro"
+        name,
+        sym::core_panic_macro
+            | sym::std_panic_macro
+            | sym::core_panic_2015_macro
+            | sym::std_panic_2015_macro
+            | sym::core_panic_2021_macro
     )
 }