diff --git a/compiler/rustc_builtin_macros/src/cfg_eval.rs b/compiler/rustc_builtin_macros/src/cfg_eval.rs index d7b46f282151..307730f7f5f1 100644 --- a/compiler/rustc_builtin_macros/src/cfg_eval.rs +++ b/compiler/rustc_builtin_macros/src/cfg_eval.rs @@ -2,6 +2,7 @@ use crate::util::check_builtin_macro_attribute; use rustc_ast as ast; use rustc_ast::mut_visit::MutVisitor; +use rustc_ast::ptr::P; use rustc_ast::tokenstream::CanSynthesizeMissingTokens; use rustc_ast::visit::Visitor; use rustc_ast::{mut_visit, visit}; @@ -9,10 +10,10 @@ use rustc_ast::{AstLike, Attribute}; use rustc_expand::base::{Annotatable, ExtCtxt}; use rustc_expand::config::StripUnconfigured; use rustc_expand::configure; +use rustc_feature::Features; use rustc_parse::parser::ForceCollect; use rustc_session::utils::FlattenNonterminals; - -use rustc_ast::ptr::P; +use rustc_session::Session; use rustc_span::symbol::sym; use rustc_span::Span; use smallvec::SmallVec; @@ -24,21 +25,19 @@ crate fn expand( annotatable: Annotatable, ) -> Vec { check_builtin_macro_attribute(ecx, meta_item, sym::cfg_eval); - vec![cfg_eval(ecx, annotatable)] + vec![cfg_eval(ecx.sess, ecx.ecfg.features, annotatable)] } -crate fn cfg_eval(ecx: &ExtCtxt<'_>, annotatable: Annotatable) -> Annotatable { - CfgEval { - cfg: &mut StripUnconfigured { - sess: ecx.sess, - features: ecx.ecfg.features, - config_tokens: true, - }, - } - .configure_annotatable(annotatable) - // Since the item itself has already been configured by the `InvocationCollector`, - // we know that fold result vector will contain exactly one element. - .unwrap() +crate fn cfg_eval( + sess: &Session, + features: Option<&Features>, + annotatable: Annotatable, +) -> Annotatable { + CfgEval { cfg: &mut StripUnconfigured { sess, features, config_tokens: true } } + .configure_annotatable(annotatable) + // Since the item itself has already been configured by the `InvocationCollector`, + // we know that fold result vector will contain exactly one element. + .unwrap() } struct CfgEval<'a, 'b> { diff --git a/compiler/rustc_builtin_macros/src/derive.rs b/compiler/rustc_builtin_macros/src/derive.rs index e0389f448ebf..241c90c15712 100644 --- a/compiler/rustc_builtin_macros/src/derive.rs +++ b/compiler/rustc_builtin_macros/src/derive.rs @@ -1,12 +1,13 @@ use crate::cfg_eval::cfg_eval; -use rustc_ast::{self as ast, attr, token, ItemKind, MetaItemKind, NestedMetaItem, StmtKind}; +use rustc_ast as ast; +use rustc_ast::{attr, token, GenericParamKind, ItemKind, MetaItemKind, NestedMetaItem, StmtKind}; use rustc_errors::{struct_span_err, Applicability}; use rustc_expand::base::{Annotatable, ExpandResult, ExtCtxt, Indeterminate, MultiItemModifier}; use rustc_feature::AttributeTemplate; use rustc_parse::validate_attr; use rustc_session::Session; -use rustc_span::symbol::sym; +use rustc_span::symbol::{sym, Ident}; use rustc_span::Span; crate struct Expander; @@ -26,8 +27,7 @@ impl MultiItemModifier for Expander { return ExpandResult::Ready(vec![item]); } - let item = cfg_eval(ecx, item); - + let (sess, features) = (ecx.sess, ecx.ecfg.features); let result = ecx.resolver.resolve_derives(ecx.current_expansion.id, ecx.force_mode, &|| { let template = @@ -40,7 +40,8 @@ impl MultiItemModifier for Expander { template, ); - attr.meta_item_list() + let mut resolutions: Vec<_> = attr + .meta_item_list() .unwrap_or_default() .into_iter() .filter_map(|nested_meta| match nested_meta { @@ -56,8 +57,21 @@ impl MultiItemModifier for Expander { report_path_args(sess, &meta); meta.path }) - .map(|path| (path, item.clone(), None)) - .collect() + .map(|path| (path, dummy_annotatable(), None)) + .collect(); + + // Do not configure or clone items unless necessary. + match &mut resolutions[..] { + [] => {} + [(_, first_item, _), others @ ..] => { + *first_item = cfg_eval(sess, features, item.clone()); + for (_, item, _) in others { + *item = first_item.clone(); + } + } + } + + resolutions }); match result { @@ -67,6 +81,18 @@ impl MultiItemModifier for Expander { } } +// The cheapest `Annotatable` to construct. +fn dummy_annotatable() -> Annotatable { + Annotatable::GenericParam(ast::GenericParam { + id: ast::DUMMY_NODE_ID, + ident: Ident::invalid(), + attrs: Default::default(), + bounds: Default::default(), + is_placeholder: false, + kind: GenericParamKind::Lifetime, + }) +} + fn report_bad_target(sess: &Session, item: &Annotatable, span: Span) -> bool { let item_kind = match item { Annotatable::Item(item) => Some(&item.kind), diff --git a/compiler/rustc_feature/src/accepted.rs b/compiler/rustc_feature/src/accepted.rs index 61e27d2e4cd4..69e0e3a01366 100644 --- a/compiler/rustc_feature/src/accepted.rs +++ b/compiler/rustc_feature/src/accepted.rs @@ -295,6 +295,8 @@ declare_features! ( (accepted, const_fn_union, "1.56.0", Some(51909), None), /// Allows explicit discriminants on non-unit enum variants. (accepted, arbitrary_enum_discriminant, "1.56.0", Some(60553), None), + /// Allows macro attributes to observe output of `#[derive]`. + (accepted, macro_attributes_in_derive_output, "1.57.0", Some(81119), None), // ------------------------------------------------------------------------- // feature-group-end: accepted features diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs index ecc2de14a791..f8b865e615c2 100644 --- a/compiler/rustc_feature/src/active.rs +++ b/compiler/rustc_feature/src/active.rs @@ -592,9 +592,6 @@ declare_features! ( /// Lessens the requirements for structs to implement `Unsize`. (active, relaxed_struct_unsize, "1.51.0", Some(81793), None), - /// Allows macro attributes to observe output of `#[derive]`. - (active, macro_attributes_in_derive_output, "1.51.0", Some(81119), None), - /// Allows associated types in inherent impls. (incomplete, inherent_associated_types, "1.52.0", Some(8995), None), diff --git a/compiler/rustc_resolve/src/macros.rs b/compiler/rustc_resolve/src/macros.rs index 4dbac47c3cc8..ddae6209a18e 100644 --- a/compiler/rustc_resolve/src/macros.rs +++ b/compiler/rustc_resolve/src/macros.rs @@ -311,38 +311,6 @@ impl<'a> ResolverExpand for Resolver<'a> { self.create_stable_hashing_context(), ); - if let Res::Def(_, _) = res { - // Gate macro attributes in `#[derive]` output. - if !self.session.features_untracked().macro_attributes_in_derive_output - && kind == MacroKind::Attr - && ext.builtin_name != Some(sym::derive) - { - let mut expn_id = parent_scope.expansion; - loop { - // Helper attr table is a quick way to determine whether the attr is `derive`. - if self.helper_attrs.contains_key(&expn_id) { - feature_err( - &self.session.parse_sess, - sym::macro_attributes_in_derive_output, - path.span, - "macro attributes in `#[derive]` output are unstable", - ) - .emit(); - break; - } else { - let expn_data = expn_id.expn_data(); - match expn_data.kind { - ExpnKind::Root - | ExpnKind::Macro(MacroKind::Bang | MacroKind::Derive, _) => { - break; - } - _ => expn_id = expn_data.parent.expect_local(), - } - } - } - } - } - Ok(ext) } diff --git a/src/test/ui/proc-macro/attribute-after-derive-feature-gate.rs b/src/test/ui/proc-macro/attribute-after-derive-feature-gate.rs deleted file mode 100644 index f0fec6782423..000000000000 --- a/src/test/ui/proc-macro/attribute-after-derive-feature-gate.rs +++ /dev/null @@ -1,37 +0,0 @@ -// gate-test-macro_attributes_in_derive_output -// aux-build: test-macros.rs - -#![feature(proc_macro_hygiene)] -#![feature(stmt_expr_attributes)] - -#[macro_use] -extern crate test_macros; - -#[derive(Empty)] -#[empty_attr] //~ ERROR macro attributes in `#[derive]` output are unstable -struct S1 { - field: [u8; 10], -} - -#[derive(Empty)] -#[empty_helper] -#[empty_attr] //~ ERROR macro attributes in `#[derive]` output are unstable -struct S2 { - field: [u8; 10], -} - -#[derive(Empty)] -struct S3 { - field: [u8; #[identity_attr] 10], //~ ERROR macro attributes in `#[derive]` output are unstable -} - -#[derive(Empty)] -struct S4 { - field: [u8; { - #[derive(Empty)] // OK, not gated - struct Inner; - 10 - }] -} - -fn main() {} diff --git a/src/test/ui/proc-macro/attribute-after-derive-feature-gate.stderr b/src/test/ui/proc-macro/attribute-after-derive-feature-gate.stderr deleted file mode 100644 index 74cace628b94..000000000000 --- a/src/test/ui/proc-macro/attribute-after-derive-feature-gate.stderr +++ /dev/null @@ -1,30 +0,0 @@ -error[E0658]: macro attributes in `#[derive]` output are unstable - --> $DIR/attribute-after-derive-feature-gate.rs:11:3 - | -LL | #[empty_attr] - | ^^^^^^^^^^ - | - = note: see issue #81119 for more information - = help: add `#![feature(macro_attributes_in_derive_output)]` to the crate attributes to enable - -error[E0658]: macro attributes in `#[derive]` output are unstable - --> $DIR/attribute-after-derive-feature-gate.rs:18:3 - | -LL | #[empty_attr] - | ^^^^^^^^^^ - | - = note: see issue #81119 for more information - = help: add `#![feature(macro_attributes_in_derive_output)]` to the crate attributes to enable - -error[E0658]: macro attributes in `#[derive]` output are unstable - --> $DIR/attribute-after-derive-feature-gate.rs:25:19 - | -LL | field: [u8; #[identity_attr] 10], - | ^^^^^^^^^^^^^ - | - = note: see issue #81119 for more information - = help: add `#![feature(macro_attributes_in_derive_output)]` to the crate attributes to enable - -error: aborting due to 3 previous errors - -For more information about this error, try `rustc --explain E0658`. diff --git a/src/test/ui/proc-macro/attribute-after-derive.rs b/src/test/ui/proc-macro/attribute-after-derive.rs index ac3f28b6ef3e..0f0f27bff97b 100644 --- a/src/test/ui/proc-macro/attribute-after-derive.rs +++ b/src/test/ui/proc-macro/attribute-after-derive.rs @@ -5,8 +5,6 @@ // compile-flags: -Z span-debug // aux-build: test-macros.rs -#![feature(macro_attributes_in_derive_output)] - #![no_std] // Don't load unnecessary hygiene information from std extern crate std; diff --git a/src/test/ui/proc-macro/attribute-after-derive.stdout b/src/test/ui/proc-macro/attribute-after-derive.stdout index 4c48e41ff338..c5b84b0367c8 100644 --- a/src/test/ui/proc-macro/attribute-after-derive.stdout +++ b/src/test/ui/proc-macro/attribute-after-derive.stdout @@ -3,35 +3,35 @@ PRINT-ATTR INPUT (DEBUG): TokenStream [ Punct { ch: '#', spacing: Alone, - span: $DIR/attribute-after-derive.rs:17:1: 17:2 (#0), + span: $DIR/attribute-after-derive.rs:15:1: 15:2 (#0), }, Group { delimiter: Bracket, stream: TokenStream [ Ident { ident: "derive", - span: $DIR/attribute-after-derive.rs:17:3: 17:9 (#0), + span: $DIR/attribute-after-derive.rs:15:3: 15:9 (#0), }, Group { delimiter: Parenthesis, stream: TokenStream [ Ident { ident: "Print", - span: $DIR/attribute-after-derive.rs:17:10: 17:15 (#0), + span: $DIR/attribute-after-derive.rs:15:10: 15:15 (#0), }, ], - span: $DIR/attribute-after-derive.rs:17:9: 17:16 (#0), + span: $DIR/attribute-after-derive.rs:15:9: 15:16 (#0), }, ], - span: $DIR/attribute-after-derive.rs:17:2: 17:17 (#0), + span: $DIR/attribute-after-derive.rs:15:2: 15:17 (#0), }, Ident { ident: "struct", - span: $DIR/attribute-after-derive.rs:18:1: 18:7 (#0), + span: $DIR/attribute-after-derive.rs:16:1: 16:7 (#0), }, Ident { ident: "AttributeDerive", - span: $DIR/attribute-after-derive.rs:18:8: 18:23 (#0), + span: $DIR/attribute-after-derive.rs:16:8: 16:23 (#0), }, Group { delimiter: Brace, @@ -39,64 +39,64 @@ PRINT-ATTR INPUT (DEBUG): TokenStream [ Punct { ch: '#', spacing: Alone, - span: $DIR/attribute-after-derive.rs:19:5: 19:6 (#0), + span: $DIR/attribute-after-derive.rs:17:5: 17:6 (#0), }, Group { delimiter: Bracket, stream: TokenStream [ Ident { ident: "cfg", - span: $DIR/attribute-after-derive.rs:19:7: 19:10 (#0), + span: $DIR/attribute-after-derive.rs:17:7: 17:10 (#0), }, Group { delimiter: Parenthesis, stream: TokenStream [ Ident { ident: "FALSE", - span: $DIR/attribute-after-derive.rs:19:11: 19:16 (#0), + span: $DIR/attribute-after-derive.rs:17:11: 17:16 (#0), }, ], - span: $DIR/attribute-after-derive.rs:19:10: 19:17 (#0), + span: $DIR/attribute-after-derive.rs:17:10: 17:17 (#0), }, ], - span: $DIR/attribute-after-derive.rs:19:6: 19:18 (#0), + span: $DIR/attribute-after-derive.rs:17:6: 17:18 (#0), }, Ident { ident: "field", - span: $DIR/attribute-after-derive.rs:20:5: 20:10 (#0), + span: $DIR/attribute-after-derive.rs:18:5: 18:10 (#0), }, Punct { ch: ':', spacing: Alone, - span: $DIR/attribute-after-derive.rs:20:10: 20:11 (#0), + span: $DIR/attribute-after-derive.rs:18:10: 18:11 (#0), }, Ident { ident: "u8", - span: $DIR/attribute-after-derive.rs:20:12: 20:14 (#0), + span: $DIR/attribute-after-derive.rs:18:12: 18:14 (#0), }, Punct { ch: ',', spacing: Alone, - span: $DIR/attribute-after-derive.rs:20:14: 20:15 (#0), + span: $DIR/attribute-after-derive.rs:18:14: 18:15 (#0), }, ], - span: $DIR/attribute-after-derive.rs:18:24: 21:2 (#0), + span: $DIR/attribute-after-derive.rs:16:24: 19:2 (#0), }, ] PRINT-DERIVE INPUT (DISPLAY): struct AttributeDerive { } PRINT-DERIVE INPUT (DEBUG): TokenStream [ Ident { ident: "struct", - span: $DIR/attribute-after-derive.rs:18:1: 18:7 (#0), + span: $DIR/attribute-after-derive.rs:16:1: 16:7 (#0), }, Ident { ident: "AttributeDerive", - span: $DIR/attribute-after-derive.rs:18:8: 18:23 (#0), + span: $DIR/attribute-after-derive.rs:16:8: 16:23 (#0), }, Group { delimiter: Brace, stream: TokenStream [], - span: $DIR/attribute-after-derive.rs:18:24: 21:2 (#0), + span: $DIR/attribute-after-derive.rs:16:24: 19:2 (#0), }, ] PRINT-DERIVE INPUT (DISPLAY): #[print_attr] struct DeriveAttribute { } @@ -104,45 +104,89 @@ PRINT-DERIVE INPUT (DEBUG): TokenStream [ Punct { ch: '#', spacing: Alone, - span: $DIR/attribute-after-derive.rs:24:1: 24:2 (#0), + span: $DIR/attribute-after-derive.rs:22:1: 22:2 (#0), }, Group { delimiter: Bracket, stream: TokenStream [ Ident { ident: "print_attr", - span: $DIR/attribute-after-derive.rs:24:3: 24:13 (#0), + span: $DIR/attribute-after-derive.rs:22:3: 22:13 (#0), }, ], - span: $DIR/attribute-after-derive.rs:24:2: 24:14 (#0), + span: $DIR/attribute-after-derive.rs:22:2: 22:14 (#0), }, Ident { ident: "struct", - span: $DIR/attribute-after-derive.rs:25:1: 25:7 (#0), + span: $DIR/attribute-after-derive.rs:23:1: 23:7 (#0), }, Ident { ident: "DeriveAttribute", - span: $DIR/attribute-after-derive.rs:25:8: 25:23 (#0), + span: $DIR/attribute-after-derive.rs:23:8: 23:23 (#0), }, Group { delimiter: Brace, stream: TokenStream [], - span: $DIR/attribute-after-derive.rs:25:24: 28:2 (#0), + span: $DIR/attribute-after-derive.rs:23:24: 26:2 (#0), }, ] -PRINT-ATTR INPUT (DISPLAY): struct DeriveAttribute { } +PRINT-ATTR INPUT (DISPLAY): struct DeriveAttribute { #[cfg(FALSE)] field : u8, } PRINT-ATTR INPUT (DEBUG): TokenStream [ Ident { ident: "struct", - span: $DIR/attribute-after-derive.rs:25:1: 25:7 (#0), + span: $DIR/attribute-after-derive.rs:23:1: 23:7 (#0), }, Ident { ident: "DeriveAttribute", - span: $DIR/attribute-after-derive.rs:25:8: 25:23 (#0), + span: $DIR/attribute-after-derive.rs:23:8: 23:23 (#0), }, Group { delimiter: Brace, - stream: TokenStream [], - span: $DIR/attribute-after-derive.rs:25:24: 28:2 (#0), + stream: TokenStream [ + Punct { + ch: '#', + spacing: Alone, + span: $DIR/attribute-after-derive.rs:24:5: 24:6 (#0), + }, + Group { + delimiter: Bracket, + stream: TokenStream [ + Ident { + ident: "cfg", + span: $DIR/attribute-after-derive.rs:24:7: 24:10 (#0), + }, + Group { + delimiter: Parenthesis, + stream: TokenStream [ + Ident { + ident: "FALSE", + span: $DIR/attribute-after-derive.rs:24:11: 24:16 (#0), + }, + ], + span: $DIR/attribute-after-derive.rs:24:10: 24:17 (#0), + }, + ], + span: $DIR/attribute-after-derive.rs:24:6: 24:18 (#0), + }, + Ident { + ident: "field", + span: $DIR/attribute-after-derive.rs:25:5: 25:10 (#0), + }, + Punct { + ch: ':', + spacing: Alone, + span: $DIR/attribute-after-derive.rs:25:10: 25:11 (#0), + }, + Ident { + ident: "u8", + span: $DIR/attribute-after-derive.rs:25:12: 25:14 (#0), + }, + Punct { + ch: ',', + spacing: Alone, + span: $DIR/attribute-after-derive.rs:25:14: 25:15 (#0), + }, + ], + span: $DIR/attribute-after-derive.rs:23:24: 26:2 (#0), }, ]