By changing some attributes to only_local, reducing encoding attributes in the crate metadate.

Thank you. This is part of changing attributes to only_local. I hope get your opinion whether I should split into multiple PRs, or submit in one. According to [try to not rely on attributes from extern crates](rust-lang/compiler-team#505) and lcnr's guidance.

Author: surechen

compiler/rustc_feature/src/builtin_attrs.rs

@@ -274,29 +274,42 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
  // ==========================================================================
 
  // Conditional compilation:
- ungated!(cfg, Normal, template!(List: "predicate"), DuplicatesOk),
- ungated!(cfg_attr, Normal, template!(List: "predicate, attr1, attr2, ..."), DuplicatesOk),
+ ungated!(cfg, Normal, template!(List: "predicate"), DuplicatesOk, @only_local: true),
+ ungated!(
+ cfg_attr, Normal, template!(List: "predicate, attr1, attr2, ..."), DuplicatesOk,
+ @only_local: true,
+ ),
 
  // Testing:
- ungated!(ignore, Normal, template!(Word, NameValueStr: "reason"), WarnFollowing),
+ ungated!(
+ ignore, Normal, template!(Word, NameValueStr: "reason"), WarnFollowing,
+ @only_local: true,
+ ),
  ungated!(
  should_panic, Normal,
  template!(Word, List: r#"expected = "reason""#, NameValueStr: "reason"), FutureWarnFollowing,
+ @only_local: true,
  ),
  // FIXME(Centril): This can be used on stable but shouldn't.
- ungated!(reexport_test_harness_main, CrateLevel, template!(NameValueStr: "name"), ErrorFollowing),
+ ungated!(
+ reexport_test_harness_main, CrateLevel, template!(NameValueStr: "name"), ErrorFollowing,
+ @only_local: true,
+ ),
 
  // Macros:
- ungated!(automatically_derived, Normal, template!(Word), WarnFollowing),
- ungated!(macro_use, Normal, template!(Word, List: "name1, name2, ..."), WarnFollowingWordOnly),
- ungated!(macro_escape, Normal, template!(Word), WarnFollowing), // Deprecated synonym for `macro_use`.
+ ungated!(automatically_derived, Normal, template!(Word), WarnFollowing, @only_local: true),
+ ungated!(
+ macro_use, Normal, template!(Word, List: "name1, name2, ..."), WarnFollowingWordOnly,
+ @only_local: true,
+ ),
+ ungated!(macro_escape, Normal, template!(Word), WarnFollowing, @only_local: true), // Deprecated synonym for `macro_use`.
  ungated!(macro_export, Normal, template!(Word, List: "local_inner_macros"), WarnFollowing),
- ungated!(proc_macro, Normal, template!(Word), ErrorFollowing),
+ ungated!(proc_macro, Normal, template!(Word), ErrorFollowing, @only_local: true),
  ungated!(
- proc_macro_derive, Normal,
- template!(List: "TraitName, /*opt*/ attributes(name1, name2, ...)"), ErrorFollowing,
+ proc_macro_derive, Normal, template!(List: "TraitName, /*opt*/ attributes(name1, name2, ...)"),
+ ErrorFollowing, @only_local: true,
  ),
- ungated!(proc_macro_attribute, Normal, template!(Word), ErrorFollowing),
+ ungated!(proc_macro_attribute, Normal, template!(Word), ErrorFollowing, @only_local: true),
 
  // Lints:
  ungated!(
@@ -309,7 +322,7 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
  ),
  gated!(
  expect, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#), DuplicatesOk,
- lint_reasons, experimental!(expect)
+ @only_local: true, lint_reasons, experimental!(expect)
  ),
  ungated!(
  forbid, Normal, template!(List: r#"lint1, lint2, ..., /*opt*/ reason = "...""#),
@@ -335,32 +348,48 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
  ),
 
  // Crate properties:
- ungated!(crate_name, CrateLevel, template!(NameValueStr: "name"), FutureWarnFollowing),
- ungated!(crate_type, CrateLevel, template!(NameValueStr: "bin|lib|..."), DuplicatesOk),
+ ungated!(
+ crate_name, CrateLevel, template!(NameValueStr: "name"), FutureWarnFollowing,
+ @only_local: true,
+ ),
+ ungated!(
+ crate_type, CrateLevel, template!(NameValueStr: "bin|lib|..."), DuplicatesOk,
+ @only_local: true,
+ ),
  // crate_id is deprecated
- ungated!(crate_id, CrateLevel, template!(NameValueStr: "ignored"), FutureWarnFollowing),
+ ungated!(
+ crate_id, CrateLevel, template!(NameValueStr: "ignored"), FutureWarnFollowing,
+ @only_local: true,
+ ),
 
  // ABI, linking, symbols, and FFI
  ungated!(
  link, Normal,
  template!(List: r#"name = "...", /*opt*/ kind = "dylib|static|...", /*opt*/ wasm_import_module = "...", /*opt*/ import_name_type = "decorated|noprefix|undecorated""#),
  DuplicatesOk,
+ @only_local: true,
  ),
  ungated!(link_name, Normal, template!(NameValueStr: "name"), FutureWarnPreceding),
- ungated!(no_link, Normal, template!(Word), WarnFollowing),
+ ungated!(no_link, Normal, template!(Word), WarnFollowing, @only_local: true),
  ungated!(repr, Normal, template!(List: "C"), DuplicatesOk, @only_local: true),
- ungated!(export_name, Normal, template!(NameValueStr: "name"), FutureWarnPreceding),
- ungated!(link_section, Normal, template!(NameValueStr: "name"), FutureWarnPreceding),
+ ungated!(export_name, Normal, template!(NameValueStr: "name"), FutureWarnPreceding, @only_local: true),
+ ungated!(link_section, Normal, template!(NameValueStr: "name"), FutureWarnPreceding, @only_local: true),
  ungated!(no_mangle, Normal, template!(Word), WarnFollowing, @only_local: true),
  ungated!(used, Normal, template!(Word, List: "compiler|linker"), WarnFollowing, @only_local: true),
  ungated!(link_ordinal, Normal, template!(List: "ordinal"), ErrorPreceding),
 
  // Limits:
- ungated!(recursion_limit, CrateLevel, template!(NameValueStr: "N"), FutureWarnFollowing),
- ungated!(type_length_limit, CrateLevel, template!(NameValueStr: "N"), FutureWarnFollowing),
+ ungated!(
+ recursion_limit, CrateLevel, template!(NameValueStr: "N"), FutureWarnFollowing,
+ @only_local: true
+ ),
+ ungated!(
+ type_length_limit, CrateLevel, template!(NameValueStr: "N"), FutureWarnFollowing,
+ @only_local: true
+ ),
  gated!(
  move_size_limit, CrateLevel, template!(NameValueStr: "N"), ErrorFollowing,
- large_assignments, experimental!(move_size_limit)
+ @only_local: true, large_assignments, experimental!(move_size_limit)
  ),
 
  // Entry point: