builtin_attrs.rs -> rustc_feature

2 files changed, 1 insertions, 595 deletions

diff --git a/src/libsyntax/feature_gate/builtin_attrs.rs b/src/libsyntax/feature_gate/builtin_attrs.rs
deleted file mode 100644
index 9b764d64c49..00000000000
--- a/src/libsyntax/feature_gate/builtin_attrs.rs
+++ /dev/null
@@ -1,594 +0,0 @@
-//! Built-in attributes and `cfg` flag gating.
-
-use AttributeType::*;
-use AttributeGate::*;
-
-use rustc_data_structures::fx::FxHashMap;
-use rustc_feature::{Features, Stability};
-use syntax_pos::symbol::{Symbol, sym};
-use lazy_static::lazy_static;
-
-type GateFn = fn(&Features) -> bool;
-
-macro_rules! cfg_fn {
-    ($field: ident) => {
-        (|features| { features.$field }) as GateFn
-    }
-}
-
-pub type GatedCfg = (Symbol, Symbol, GateFn);
-
-/// `cfg(...)`'s that are feature gated.
-const GATED_CFGS: &[GatedCfg] = &[
-    // (name in cfg, feature, function to check if the feature is enabled)
-    (sym::target_thread_local, sym::cfg_target_thread_local, cfg_fn!(cfg_target_thread_local)),
-    (sym::target_has_atomic, sym::cfg_target_has_atomic, cfg_fn!(cfg_target_has_atomic)),
-    (sym::target_has_atomic_load_store, sym::cfg_target_has_atomic, cfg_fn!(cfg_target_has_atomic)),
-];
-
-/// Find a gated cfg determined by the `pred`icate which is given the cfg's name.
-pub fn find_gated_cfg(pred: impl Fn(Symbol) -> bool) -> Option<&'static GatedCfg> {
-    GATED_CFGS.iter().find(|(cfg_sym, ..)| pred(*cfg_sym))
-}
-
-// If you change this, please modify `src/doc/unstable-book` as well. You must
-// move that documentation into the relevant place in the other docs, and
-// remove the chapter on the flag.
-
-#[derive(Copy, Clone, PartialEq, Debug)]
-pub enum AttributeType {
-    /// Normal, builtin attribute that is consumed
-    /// by the compiler before the unused_attribute check
-    Normal,
-
-    /// Builtin attribute that may not be consumed by the compiler
-    /// before the unused_attribute check. These attributes
-    /// will be ignored by the unused_attribute lint
-    Whitelisted,
-
-    /// Builtin attribute that is only allowed at the crate level
-    CrateLevel,
-}
-
-#[derive(Clone, Copy)]
-pub enum AttributeGate {
-    /// Is gated by a given feature gate, reason
-    /// and function to check if enabled
-    Gated(Stability, Symbol, &'static str, fn(&Features) -> bool),
-
-    /// Ungated attribute, can be used on all release channels
-    Ungated,
-}
-
-// fn() is not Debug
-impl std::fmt::Debug for AttributeGate {
-    fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        match *self {
-            Self::Gated(ref stab, name, expl, _) =>
-                write!(fmt, "Gated({:?}, {}, {})", stab, name, expl),
-            Self::Ungated => write!(fmt, "Ungated")
-        }
-    }
-}
-
-impl AttributeGate {
-    fn is_deprecated(&self) -> bool {
-        match *self {
-            Self::Gated(Stability::Deprecated(_, _), ..) => true,
-            _ => false,
-        }
-    }
-}
-
-/// A template that the attribute input must match.
-/// Only top-level shape (`#[attr]` vs `#[attr(...)]` vs `#[attr = ...]`) is considered now.
-#[derive(Clone, Copy)]
-pub struct AttributeTemplate {
-    pub word: bool,
-    pub list: Option<&'static str>,
-    pub name_value_str: Option<&'static str>,
-}
-
-impl AttributeTemplate {
-    pub fn only_word() -> Self {
-        Self { word: true, list: None, name_value_str: None }
-    }
-}
-
-/// A convenience macro for constructing attribute templates.
-/// E.g., `template!(Word, List: "description")` means that the attribute
-/// supports forms `#[attr]` and `#[attr(description)]`.
-macro_rules! template {
-    (Word) => { template!(@ true, None, None) };
-    (List: $descr: expr) => { template!(@ false, Some($descr), None) };
-    (NameValueStr: $descr: expr) => { template!(@ false, None, Some($descr)) };
-    (Word, List: $descr: expr) => { template!(@ true, Some($descr), None) };
-    (Word, NameValueStr: $descr: expr) => { template!(@ true, None, Some($descr)) };
-    (List: $descr1: expr, NameValueStr: $descr2: expr) => {
-        template!(@ false, Some($descr1), Some($descr2))
-    };
-    (Word, List: $descr1: expr, NameValueStr: $descr2: expr) => {
-        template!(@ true, Some($descr1), Some($descr2))
-    };
-    (@ $word: expr, $list: expr, $name_value_str: expr) => { AttributeTemplate {
-        word: $word, list: $list, name_value_str: $name_value_str
-    } };
-}
-
-macro_rules! ungated {
-    ($attr:ident, $typ:expr, $tpl:expr $(,)?) => {
-        (sym::$attr, $typ, $tpl, Ungated)
-    };
-}
-
-macro_rules! gated {
-    ($attr:ident, $typ:expr, $tpl:expr, $gate:ident, $msg:expr $(,)?) => {
-        (sym::$attr, $typ, $tpl, Gated(Stability::Unstable, sym::$gate, $msg, cfg_fn!($gate)))
-    };
-    ($attr:ident, $typ:expr, $tpl:expr, $msg:expr $(,)?) => {
-        (sym::$attr, $typ, $tpl, Gated(Stability::Unstable, sym::$attr, $msg, cfg_fn!($attr)))
-    };
-}
-
-macro_rules! rustc_attr {
-    (TEST, $attr:ident, $typ:expr, $tpl:expr $(,)?) => {
-        rustc_attr!(
-            $attr, $typ, $tpl,
-            concat!("the `#[", stringify!($attr), "]` attribute is just used for rustc unit tests \
-                and will never be stable",
-            ),
-        )
-    };
-    ($attr:ident, $typ:expr, $tpl:expr, $msg:expr $(,)?) => {
-        (sym::$attr, $typ, $tpl,
-         Gated(Stability::Unstable, sym::rustc_attrs, $msg, cfg_fn!(rustc_attrs)))
-    };
-}
-
-macro_rules! experimental {
-    ($attr:ident) => {
-        concat!("the `#[", stringify!($attr), "]` attribute is an experimental feature")
-    }
-}
-
-const IMPL_DETAIL: &str = "internal implementation detail";
-const INTERNAL_UNSTABLE: &str = "this is an internal attribute that will never be stable";
-
-pub type BuiltinAttribute = (Symbol, AttributeType, AttributeTemplate, AttributeGate);
-
-/// Attributes that have a special meaning to rustc or rustdoc.
-pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
-    // ==========================================================================
-    // Stable attributes:
-    // ==========================================================================
-
-    // Condtional compilation:
-    ungated!(cfg, Normal, template!(List: "predicate")),
-    ungated!(cfg_attr, Normal, template!(List: "predicate, attr1, attr2, ...")),
-
-    // Testing:
-    ungated!(ignore, Normal, template!(Word, NameValueStr: "reason")),
-    ungated!(
-        should_panic, Normal,
-        template!(Word, List: r#"expected = "reason"#, NameValueStr: "reason"),
-    ),
-    // FIXME(Centril): This can be used on stable but shouldn't.
-    ungated!(reexport_test_harness_main, Normal, template!(NameValueStr: "name")),
-
-    // Macros:
-    ungated!(derive, Normal, template!(List: "Trait1, Trait2, ...")),
-    ungated!(automatically_derived, Normal, template!(Word)),
-    // FIXME(#14407)
-    ungated!(macro_use, Normal, template!(Word, List: "name1, name2, ...")),
-    ungated!(macro_escape, Normal, template!(Word)), // Deprecated synonym for `macro_use`.
-    ungated!(macro_export, Normal, template!(Word, List: "local_inner_macros")),
-    ungated!(proc_macro, Normal, template!(Word)),
-    ungated!(
-        proc_macro_derive, Normal,
-        template!(List: "TraitName, /*opt*/ attributes(name1, name2, ...)"),
-    ),
-    ungated!(proc_macro_attribute, Normal, template!(Word)),
-
-    // Lints:
-    ungated!(warn, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#)),
-    ungated!(allow, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#)),
-    ungated!(forbid, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#)),
-    ungated!(deny, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#)),
-    ungated!(must_use, Whitelisted, template!(Word, NameValueStr: "reason")),
-    // FIXME(#14407)
-    ungated!(
-        deprecated, Normal,
-        template!(
-            Word,
-            List: r#"/*opt*/ since = "version", /*opt*/ note = "reason""#,
-            NameValueStr: "reason"
-        ),
-    ),
-
-    // Crate properties:
-    ungated!(crate_name, CrateLevel, template!(NameValueStr: "name")),
-    ungated!(crate_type, CrateLevel, template!(NameValueStr: "bin|lib|...")),
-    ungated!(crate_id, CrateLevel, template!(NameValueStr: "ignored")),
-
-    // ABI, linking, symbols, and FFI
-    ungated!(
-        link, Whitelisted,
-        template!(List: r#"name = "...", /*opt*/ kind = "dylib|static|...", /*opt*/ cfg = "...""#),
-    ),
-    ungated!(link_name, Whitelisted, template!(NameValueStr: "name")),
-    ungated!(no_link, Normal, template!(Word)),
-    ungated!(repr, Normal, template!(List: "C")),
-    ungated!(export_name, Whitelisted, template!(NameValueStr: "name")),
-    ungated!(link_section, Whitelisted, template!(NameValueStr: "name")),
-    ungated!(no_mangle, Whitelisted, template!(Word)),
-    ungated!(used, Whitelisted, template!(Word)),
-
-    // Limits:
-    ungated!(recursion_limit, CrateLevel, template!(NameValueStr: "N")),
-    ungated!(type_length_limit, CrateLevel, template!(NameValueStr: "N")),
-
-    // Entry point:
-    ungated!(main, Normal, template!(Word)),
-    ungated!(start, Normal, template!(Word)),
-    ungated!(no_start, CrateLevel, template!(Word)),
-    ungated!(no_main, CrateLevel, template!(Word)),
-
-    // Modules, prelude, and resolution:
-    ungated!(path, Normal, template!(NameValueStr: "file")),
-    ungated!(no_std, CrateLevel, template!(Word)),
-    ungated!(no_implicit_prelude, Normal, template!(Word)),
-    ungated!(non_exhaustive, Whitelisted, template!(Word)),
-
-    // Runtime
-    ungated!(windows_subsystem, Whitelisted, template!(NameValueStr: "windows|console")),
-    ungated!(panic_handler, Normal, template!(Word)), // RFC 2070
-
-    // Code generation:
-    ungated!(inline, Whitelisted, template!(Word, List: "always|never")),
-    ungated!(cold, Whitelisted, template!(Word)),
-    ungated!(no_builtins, Whitelisted, template!(Word)),
-    ungated!(target_feature, Whitelisted, template!(List: r#"enable = "name""#)),
-
-    // FIXME: #14408 whitelist docs since rustdoc looks at them
-    ungated!(doc, Whitelisted, template!(List: "hidden|inline|...", NameValueStr: "string")),
-
-    // ==========================================================================
-    // Unstable attributes:
-    // ==========================================================================
-
-    // Linking:
-    gated!(naked, Whitelisted, template!(Word), naked_functions, experimental!(naked)),
-    gated!(
-        link_args, Normal, template!(NameValueStr: "args"),
-        "the `link_args` attribute is experimental and not portable across platforms, \
-        it is recommended to use `#[link(name = \"foo\")] instead",
-    ),
-    gated!(
-        link_ordinal, Whitelisted, template!(List: "ordinal"), raw_dylib,
-        experimental!(link_ordinal)
-    ),
-
-    // Plugins:
-    (
-        sym::plugin_registrar, Normal, template!(Word),
-        Gated(
-            Stability::Deprecated(
-                "https://github.com/rust-lang/rust/pull/64675",
-                Some("may be removed in a future compiler version"),
-            ),
-            sym::plugin_registrar,
-            "compiler plugins are deprecated",
-            cfg_fn!(plugin_registrar)
-        )
-    ),
-    (
-        sym::plugin, CrateLevel, template!(List: "name|name(args)"),
-        Gated(
-            Stability::Deprecated(
-                "https://github.com/rust-lang/rust/pull/64675",
-                Some("may be removed in a future compiler version"),
-            ),
-            sym::plugin,
-            "compiler plugins are deprecated",
-            cfg_fn!(plugin)
-        )
-    ),
-
-    // Testing:
-    gated!(allow_fail, Normal, template!(Word), experimental!(allow_fail)),
-    gated!(
-        test_runner, CrateLevel, template!(List: "path"), custom_test_frameworks,
-        "custom test frameworks are an unstable feature",
-    ),
-    // RFC #1268
-    gated!(marker, Normal, template!(Word), marker_trait_attr, experimental!(marker)),
-    gated!(
-        thread_local, Whitelisted, template!(Word),
-        "`#[thread_local]` is an experimental feature, and does not currently handle destructors",
-    ),
-    gated!(no_core, CrateLevel, template!(Word), experimental!(no_core)),
-    // RFC 2412
-    gated!(
-        optimize, Whitelisted, template!(List: "size|speed"), optimize_attribute,
-        experimental!(optimize),
-    ),
-
-    gated!(ffi_returns_twice, Whitelisted, template!(Word), experimental!(ffi_returns_twice)),
-    gated!(track_caller, Whitelisted, template!(Word), experimental!(track_caller)),
-    gated!(
-        register_attr, CrateLevel, template!(List: "attr1, attr2, ..."),
-        experimental!(register_attr),
-    ),
-    gated!(
-        register_tool, CrateLevel, template!(List: "tool1, tool2, ..."),
-        experimental!(register_tool),
-    ),
-
-    // ==========================================================================
-    // Internal attributes: Stability, deprecation, and unsafe:
-    // ==========================================================================
-
-    ungated!(feature, CrateLevel, template!(List: "name1, name1, ...")),
-    // FIXME(#14407) -- only looked at on-demand so we can't
-    // guarantee they'll have already been checked.
-    ungated!(
-        rustc_deprecated, Whitelisted,
-        template!(List: r#"since = "version", reason = "...""#)
-    ),
-    // FIXME(#14407)
-    ungated!(stable, Whitelisted, template!(List: r#"feature = "name", since = "version""#)),
-    // FIXME(#14407)
-    ungated!(
-        unstable, Whitelisted,
-        template!(List: r#"feature = "name", reason = "...", issue = "N""#),
-    ),
-    gated!(
-        rustc_const_unstable, Normal, template!(List: r#"feature = "name""#),
-        "the `#[rustc_const_unstable]` attribute is an internal feature",
-    ),
-    gated!(
-        allow_internal_unstable, Normal, template!(Word, List: "feat1, feat2, ..."),
-        "allow_internal_unstable side-steps feature gating and stability checks",
-    ),
-    gated!(
-        allow_internal_unsafe, Normal, template!(Word),
-        "allow_internal_unsafe side-steps the unsafe_code lint",
-    ),
-
-    // ==========================================================================
-    // Internal attributes: Type system related:
-    // ==========================================================================
-
-    gated!(fundamental, Whitelisted, template!(Word), experimental!(fundamental)),
-    gated!(
-        // RFC #1445.
-        structural_match, Whitelisted, template!(Word),
-        "the semantics of constant patterns is not yet settled",
-    ),
-    gated!(
-        may_dangle, Normal, template!(Word), dropck_eyepatch,
-        "`may_dangle` has unstable semantics and may be removed in the future",
-    ),
-
-    // ==========================================================================
-    // Internal attributes: Runtime related:
-    // ==========================================================================
-
-    rustc_attr!(rustc_allocator, Whitelisted, template!(Word), IMPL_DETAIL),
-    rustc_attr!(rustc_allocator_nounwind, Whitelisted, template!(Word), IMPL_DETAIL),
-    gated!(alloc_error_handler, Normal, template!(Word), experimental!(alloc_error_handler)),
-    gated!(
-        default_lib_allocator, Whitelisted, template!(Word), allocator_internals,
-        experimental!(default_lib_allocator),
-    ),
-    gated!(
-        needs_allocator, Normal, template!(Word), allocator_internals,
-        experimental!(needs_allocator),
-    ),
-    gated!(panic_runtime, Whitelisted, template!(Word), experimental!(panic_runtime)),
-    gated!(needs_panic_runtime, Whitelisted, template!(Word), experimental!(needs_panic_runtime)),
-    gated!(
-        unwind, Whitelisted, template!(List: "allowed|aborts"), unwind_attributes,
-        experimental!(unwind),
-    ),
-    gated!(
-        compiler_builtins, Whitelisted, template!(Word),
-        "the `#[compiler_builtins]` attribute is used to identify the `compiler_builtins` crate \
-        which contains compiler-rt intrinsics and will never be stable",
-    ),
-    gated!(
-        sanitizer_runtime, Whitelisted, template!(Word),
-        "the `#[sanitizer_runtime]` attribute is used to identify crates that contain the runtime \
-        of a sanitizer and will never be stable",
-    ),
-    gated!(
-        profiler_runtime, Whitelisted, template!(Word),
-        "the `#[profiler_runtime]` attribute is used to identify the `profiler_builtins` crate \
-        which contains the profiler runtime and will never be stable",
-    ),
-
-    // ==========================================================================
-    // Internal attributes, Linkage:
-    // ==========================================================================
-
-    gated!(
-        linkage, Whitelisted, template!(NameValueStr: "external|internal|..."),
-        "the `linkage` attribute is experimental and not portable across platforms",
-    ),
-    rustc_attr!(rustc_std_internal_symbol, Whitelisted, template!(Word), INTERNAL_UNSTABLE),
-
-    // ==========================================================================
-    // Internal attributes, Macro related:
-    // ==========================================================================
-
-    rustc_attr!(rustc_builtin_macro, Whitelisted, template!(Word), IMPL_DETAIL),
-    rustc_attr!(rustc_proc_macro_decls, Normal, template!(Word), INTERNAL_UNSTABLE),
-    rustc_attr!(
-        rustc_macro_transparency, Whitelisted,
-        template!(NameValueStr: "transparent|semitransparent|opaque"),
-        "used internally for testing macro hygiene",
-    ),
-
-    // ==========================================================================
-    // Internal attributes, Diagnostics related:
-    // ==========================================================================
-
-    rustc_attr!(
-        rustc_on_unimplemented, Whitelisted,
-        template!(
-            List: r#"/*opt*/ message = "...", /*opt*/ label = "...", /*opt*/ note = "...""#,
-            NameValueStr: "message"
-        ),
-        INTERNAL_UNSTABLE
-    ),
-    // Whitelists "identity-like" conversion methods to suggest on type mismatch.
-    rustc_attr!(rustc_conversion_suggestion, Whitelisted, template!(Word), INTERNAL_UNSTABLE),
-
-    // ==========================================================================
-    // Internal attributes, Const related:
-    // ==========================================================================
-
-    rustc_attr!(rustc_promotable, Whitelisted, template!(Word), IMPL_DETAIL),
-    rustc_attr!(rustc_allow_const_fn_ptr, Whitelisted, template!(Word), IMPL_DETAIL),
-    rustc_attr!(rustc_args_required_const, Whitelisted, template!(List: "N"), INTERNAL_UNSTABLE),
-
-    // ==========================================================================
-    // Internal attributes, Layout related:
-    // ==========================================================================
-
-    rustc_attr!(
-        rustc_layout_scalar_valid_range_start, Whitelisted, template!(List: "value"),
-        "the `#[rustc_layout_scalar_valid_range_start]` attribute is just used to enable \
-        niche optimizations in libcore and will never be stable",
-    ),
-    rustc_attr!(
-        rustc_layout_scalar_valid_range_end, Whitelisted, template!(List: "value"),
-        "the `#[rustc_layout_scalar_valid_range_end]` attribute is just used to enable \
-        niche optimizations in libcore and will never be stable",
-    ),
-    rustc_attr!(
-        rustc_nonnull_optimization_guaranteed, Whitelisted, template!(Word),
-        "the `#[rustc_nonnull_optimization_guaranteed]` attribute is just used to enable \
-        niche optimizations in libcore and will never be stable",
-    ),
-
-    // ==========================================================================
-    // Internal attributes, Misc:
-    // ==========================================================================
-    gated!(
-        lang, Normal, template!(NameValueStr: "name"), lang_items,
-        "language items are subject to change",
-    ),
-    (
-        sym::rustc_diagnostic_item,
-        Normal,
-        template!(NameValueStr: "name"),
-        Gated(
-            Stability::Unstable,
-            sym::rustc_attrs,
-            "diagnostic items compiler internal support for linting",
-            cfg_fn!(rustc_attrs),
-        ),
-    ),
-    (
-        sym::no_debug, Whitelisted, template!(Word),
-        Gated(
-            Stability::Deprecated("https://github.com/rust-lang/rust/issues/29721", None),
-            sym::no_debug,
-            "the `#[no_debug]` attribute was an experimental feature that has been \
-            deprecated due to lack of demand",
-            cfg_fn!(no_debug)
-        )
-    ),
-    gated!(
-        // Used in resolve:
-        prelude_import, Whitelisted, template!(Word),
-        "`#[prelude_import]` is for use by rustc only",
-    ),
-    gated!(
-        rustc_paren_sugar, Normal, template!(Word), unboxed_closures,
-        "unboxed_closures are still evolving",
-    ),
-    rustc_attr!(
-        rustc_inherit_overflow_checks, Whitelisted, template!(Word),
-        "the `#[rustc_inherit_overflow_checks]` attribute is just used to control \
-        overflow checking behavior of several libcore functions that are inlined \
-        across crates and will never be stable",
-    ),
-    rustc_attr!(rustc_reservation_impl, Normal, template!(NameValueStr: "reservation message"),
-                "the `#[rustc_reservation_impl]` attribute is internally used \
-                 for reserving for `for<T> From<!> for T` impl"
-    ),
-    rustc_attr!(
-        rustc_test_marker, Normal, template!(Word),
-        "the `#[rustc_test_marker]` attribute is used internally to track tests",
-    ),
-
-    // ==========================================================================
-    // Internal attributes, Testing:
-    // ==========================================================================
-
-    rustc_attr!(TEST, rustc_outlives, Normal, template!(Word)),
-    rustc_attr!(TEST, rustc_variance, Normal, template!(Word)),
-    rustc_attr!(TEST, rustc_layout, Normal, template!(List: "field1, field2, ...")),
-    rustc_attr!(TEST, rustc_regions, Normal, template!(Word)),
-    rustc_attr!(
-        TEST, rustc_error, Whitelisted,
-        template!(Word, List: "delay_span_bug_from_inside_query")
-    ),
-    rustc_attr!(TEST, rustc_dump_user_substs, Whitelisted, template!(Word)),
-    rustc_attr!(TEST, rustc_if_this_changed, Whitelisted, template!(Word, List: "DepNode")),
-    rustc_attr!(TEST, rustc_then_this_would_need, Whitelisted, template!(List: "DepNode")),
-    rustc_attr!(
-        TEST, rustc_dirty, Whitelisted,
-        template!(List: r#"cfg = "...", /*opt*/ label = "...", /*opt*/ except = "...""#),
-    ),
-    rustc_attr!(
-        TEST, rustc_clean, Whitelisted,
-        template!(List: r#"cfg = "...", /*opt*/ label = "...", /*opt*/ except = "...""#),
-    ),
-    rustc_attr!(
-        TEST, rustc_partition_reused, Whitelisted,
-        template!(List: r#"cfg = "...", module = "...""#),
-    ),
-    rustc_attr!(
-        TEST, rustc_partition_codegened, Whitelisted,
-        template!(List: r#"cfg = "...", module = "...""#),
-    ),
-    rustc_attr!(
-        TEST, rustc_expected_cgu_reuse, Whitelisted,
-        template!(List: r#"cfg = "...", module = "...", kind = "...""#),
-    ),
-    rustc_attr!(TEST, rustc_synthetic, Whitelisted, template!(Word)),
-    rustc_attr!(TEST, rustc_symbol_name, Whitelisted, template!(Word)),
-    rustc_attr!(TEST, rustc_def_path, Whitelisted, template!(Word)),
-    rustc_attr!(TEST, rustc_mir, Whitelisted, template!(List: "arg1, arg2, ...")),
-    rustc_attr!(TEST, rustc_dump_program_clauses, Whitelisted, template!(Word)),
-    rustc_attr!(TEST, rustc_dump_env_program_clauses, Whitelisted, template!(Word)),
-    rustc_attr!(TEST, rustc_object_lifetime_default, Whitelisted, template!(Word)),
-    rustc_attr!(TEST, rustc_dummy, Normal, template!(Word /* doesn't matter*/)),
-    gated!(
-        omit_gdb_pretty_printer_section, Whitelisted, template!(Word),
-        "the `#[omit_gdb_pretty_printer_section]` attribute is just used for the Rust test suite",
-    ),
-];
-
-pub fn deprecated_attributes() -> Vec<&'static BuiltinAttribute> {
-    BUILTIN_ATTRIBUTES.iter().filter(|(.., gate)| gate.is_deprecated()).collect()
-}
-
-pub fn is_builtin_attr_name(name: Symbol) -> bool {
-    BUILTIN_ATTRIBUTE_MAP.get(&name).is_some()
-}
-
-lazy_static! {
-    pub static ref BUILTIN_ATTRIBUTE_MAP: FxHashMap<Symbol, &'static BuiltinAttribute> = {
-        let mut map = FxHashMap::default();
-        for attr in BUILTIN_ATTRIBUTES.iter() {
-            if map.insert(attr.0, attr).is_some() {
-                panic!("duplicate builtin attribute `{}`", attr.0);
-            }
-        }
-        map
-    };
-}
diff --git a/src/libsyntax/feature_gate/check.rs b/src/libsyntax/feature_gate/check.rs
index e89c1f910d3..b5dc7d4db2b 100644
--- a/src/libsyntax/feature_gate/check.rs
+++ b/src/libsyntax/feature_gate/check.rs
@@ -1,6 +1,6 @@
 use rustc_feature::{ACCEPTED_FEATURES, ACTIVE_FEATURES, Features, Feature, State as FeatureState};
 use rustc_feature::{REMOVED_FEATURES, STABLE_REMOVED_FEATURES};
-use super::builtin_attrs::{AttributeGate, BUILTIN_ATTRIBUTE_MAP};
+use rustc_feature::{AttributeGate, BUILTIN_ATTRIBUTE_MAP};
 
 use crate::ast::{self, AssocTyConstraint, AssocTyConstraintKind, NodeId};
 use crate::ast::{GenericParam, GenericParamKind, PatKind, RangeEnd, VariantData};