diff options
Diffstat (limited to 'compiler/rustc_expand/src')
| -rw-r--r-- | compiler/rustc_expand/src/base.rs | 40 | ||||
| -rw-r--r-- | compiler/rustc_expand/src/expand.rs | 11 | ||||
| -rw-r--r-- | compiler/rustc_expand/src/mbe/macro_check.rs | 11 | ||||
| -rw-r--r-- | compiler/rustc_expand/src/mbe/macro_rules.rs | 86 |
4 files changed, 102 insertions, 46 deletions
diff --git a/compiler/rustc_expand/src/base.rs b/compiler/rustc_expand/src/base.rs index 3956125bace..810a5a21a05 100644 --- a/compiler/rustc_expand/src/base.rs +++ b/compiler/rustc_expand/src/base.rs @@ -10,7 +10,7 @@ use rustc_ast::attr::{AttributeExt, MarkedAttrs}; use rustc_ast::token::MetaVarKind; use rustc_ast::tokenstream::TokenStream; use rustc_ast::visit::{AssocCtxt, Visitor}; -use rustc_ast::{self as ast, AttrVec, Attribute, HasAttrs, Item, NodeId, PatKind}; +use rustc_ast::{self as ast, AttrVec, Attribute, HasAttrs, Item, NodeId, PatKind, Safety}; use rustc_data_structures::fx::{FxHashMap, FxIndexMap}; use rustc_data_structures::sync; use rustc_errors::{BufferedEarlyLint, DiagCtxtHandle, ErrorGuaranteed, PResult}; @@ -324,16 +324,16 @@ pub trait BangProcMacro { impl<F> BangProcMacro for F where - F: Fn(TokenStream) -> TokenStream, + F: Fn(&mut ExtCtxt<'_>, Span, TokenStream) -> Result<TokenStream, ErrorGuaranteed>, { fn expand<'cx>( &self, - _ecx: &'cx mut ExtCtxt<'_>, - _span: Span, + ecx: &'cx mut ExtCtxt<'_>, + span: Span, ts: TokenStream, ) -> Result<TokenStream, ErrorGuaranteed> { // FIXME setup implicit context in TLS before calling self. - Ok(self(ts)) + self(ecx, span, ts) } } @@ -345,6 +345,21 @@ pub trait AttrProcMacro { annotation: TokenStream, annotated: TokenStream, ) -> Result<TokenStream, ErrorGuaranteed>; + + // Default implementation for safe attributes; override if the attribute can be unsafe. + fn expand_with_safety<'cx>( + &self, + ecx: &'cx mut ExtCtxt<'_>, + safety: Safety, + span: Span, + annotation: TokenStream, + annotated: TokenStream, + ) -> Result<TokenStream, ErrorGuaranteed> { + if let Safety::Unsafe(span) = safety { + ecx.dcx().span_err(span, "unnecessary `unsafe` on safe attribute"); + } + self.expand(ecx, span, annotation, annotated) + } } impl<F> AttrProcMacro for F @@ -999,17 +1014,14 @@ impl SyntaxExtension { /// A dummy bang macro `foo!()`. pub fn dummy_bang(edition: Edition) -> SyntaxExtension { - fn expander<'cx>( - cx: &'cx mut ExtCtxt<'_>, + fn expand( + ecx: &mut ExtCtxt<'_>, span: Span, - _: TokenStream, - ) -> MacroExpanderResult<'cx> { - ExpandResult::Ready(DummyResult::any( - span, - cx.dcx().span_delayed_bug(span, "expanded a dummy bang macro"), - )) + _ts: TokenStream, + ) -> Result<TokenStream, ErrorGuaranteed> { + Err(ecx.dcx().span_delayed_bug(span, "expanded a dummy bang macro")) } - SyntaxExtension::default(SyntaxExtensionKind::LegacyBang(Arc::new(expander)), edition) + SyntaxExtension::default(SyntaxExtensionKind::Bang(Arc::new(expand)), edition) } /// A dummy derive macro `#[derive(Foo)]`. diff --git a/compiler/rustc_expand/src/expand.rs b/compiler/rustc_expand/src/expand.rs index 4c0e0bbfe26..3dfa3cdcc35 100644 --- a/compiler/rustc_expand/src/expand.rs +++ b/compiler/rustc_expand/src/expand.rs @@ -812,11 +812,12 @@ impl<'a, 'b> MacroExpander<'a, 'b> { _ => item.to_tokens(), }; let attr_item = attr.get_normal_item(); + let safety = attr_item.unsafety; if let AttrArgs::Eq { .. } = attr_item.args { self.cx.dcx().emit_err(UnsupportedKeyValue { span }); } let inner_tokens = attr_item.args.inner_tokens(); - match expander.expand(self.cx, span, inner_tokens, tokens) { + match expander.expand_with_safety(self.cx, safety, span, inner_tokens, tokens) { Ok(tok_result) => { let fragment = self.parse_ast_fragment( tok_result, @@ -840,6 +841,9 @@ impl<'a, 'b> MacroExpander<'a, 'b> { Err(guar) => return ExpandResult::Ready(fragment_kind.dummy(span, guar)), } } else if let SyntaxExtensionKind::LegacyAttr(expander) = ext { + // `LegacyAttr` is only used for builtin attribute macros, which have their + // safety checked by `check_builtin_meta_item`, so we don't need to check + // `unsafety` here. match validate_attr::parse_meta(&self.cx.sess.psess, &attr) { Ok(meta) => { let item_clone = macro_stats.then(|| item.clone()); @@ -882,6 +886,9 @@ impl<'a, 'b> MacroExpander<'a, 'b> { } } } else if let SyntaxExtensionKind::NonMacroAttr = ext { + if let ast::Safety::Unsafe(span) = attr.get_normal_item().unsafety { + self.cx.dcx().span_err(span, "unnecessary `unsafe` on safe attribute"); + } // `-Zmacro-stats` ignores these because they don't do any real expansion. self.cx.expanded_inert_attrs.mark(&attr); item.visit_attrs(|attrs| attrs.insert(pos, attr)); @@ -971,7 +978,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> { }); } }, - SyntaxExtensionKind::LegacyBang(..) => { + SyntaxExtensionKind::Bang(..) => { let msg = "expanded a dummy glob delegation"; let guar = self.cx.dcx().span_delayed_bug(span, msg); return ExpandResult::Ready(fragment_kind.dummy(span, guar)); diff --git a/compiler/rustc_expand/src/mbe/macro_check.rs b/compiler/rustc_expand/src/mbe/macro_check.rs index ebd6e887f7d..0eae44a05e7 100644 --- a/compiler/rustc_expand/src/mbe/macro_check.rs +++ b/compiler/rustc_expand/src/mbe/macro_check.rs @@ -210,8 +210,7 @@ pub(super) fn check_meta_variables( guar.map_or(Ok(()), Err) } -/// Checks `lhs` as part of the LHS of a macro definition, extends `binders` with new binders, and -/// sets `valid` to false in case of errors. +/// Checks `lhs` as part of the LHS of a macro definition. /// /// Arguments: /// - `psess` is used to emit diagnostics and lints @@ -306,8 +305,7 @@ fn get_binder_info<'a>( binders.get(&name).or_else(|| macros.find_map(|state| state.binders.get(&name))) } -/// Checks `rhs` as part of the RHS of a macro definition and sets `valid` to false in case of -/// errors. +/// Checks `rhs` as part of the RHS of a macro definition. /// /// Arguments: /// - `psess` is used to emit diagnostics and lints @@ -372,7 +370,7 @@ enum NestedMacroState { } /// Checks `tts` as part of the RHS of a macro definition, tries to recognize nested macro -/// definitions, and sets `valid` to false in case of errors. +/// definitions. /// /// Arguments: /// - `psess` is used to emit diagnostics and lints @@ -491,8 +489,7 @@ fn check_nested_occurrences( } } -/// Checks the body of nested macro, returns where the check stopped, and sets `valid` to false in -/// case of errors. +/// Checks the body of nested macro, returns where the check stopped. /// /// The token trees are checked as long as they look like a list of (LHS) => {RHS} token trees. This /// check is a best-effort to detect a macro definition. It returns the position in `tts` where we diff --git a/compiler/rustc_expand/src/mbe/macro_rules.rs b/compiler/rustc_expand/src/mbe/macro_rules.rs index 1d147a0385c..c548cea537f 100644 --- a/compiler/rustc_expand/src/mbe/macro_rules.rs +++ b/compiler/rustc_expand/src/mbe/macro_rules.rs @@ -8,7 +8,7 @@ use rustc_ast::token::NtPatKind::*; use rustc_ast::token::TokenKind::*; use rustc_ast::token::{self, Delimiter, NonterminalKind, Token, TokenKind}; use rustc_ast::tokenstream::{self, DelimSpan, TokenStream}; -use rustc_ast::{self as ast, DUMMY_NODE_ID, NodeId}; +use rustc_ast::{self as ast, DUMMY_NODE_ID, NodeId, Safety}; use rustc_ast_pretty::pprust; use rustc_data_structures::fx::{FxHashMap, FxIndexMap}; use rustc_errors::{Applicability, Diag, ErrorGuaranteed, MultiSpan}; @@ -33,8 +33,8 @@ use super::diagnostics::{FailedMacro, failed_to_match_macro}; use super::macro_parser::{NamedMatches, NamedParseResult}; use super::{SequenceRepetition, diagnostics}; use crate::base::{ - AttrProcMacro, DummyResult, ExpandResult, ExtCtxt, MacResult, MacroExpanderResult, - SyntaxExtension, SyntaxExtensionKind, TTMacroExpander, + AttrProcMacro, BangProcMacro, DummyResult, ExpandResult, ExtCtxt, MacResult, + MacroExpanderResult, SyntaxExtension, SyntaxExtensionKind, TTMacroExpander, }; use crate::errors; use crate::expand::{AstFragment, AstFragmentKind, ensure_complete_parse, parse_ast_fragment}; @@ -131,6 +131,7 @@ pub(super) enum MacroRule { Func { lhs: Vec<MatcherLoc>, lhs_span: Span, rhs: mbe::TokenTree }, /// An attr rule, for use with `#[m]` Attr { + unsafe_rule: bool, args: Vec<MatcherLoc>, args_span: Span, body: Vec<MatcherLoc>, @@ -248,7 +249,18 @@ impl TTMacroExpander for MacroRulesMacroExpander { impl AttrProcMacro for MacroRulesMacroExpander { fn expand( &self, + _cx: &mut ExtCtxt<'_>, + _sp: Span, + _args: TokenStream, + _body: TokenStream, + ) -> Result<TokenStream, ErrorGuaranteed> { + unreachable!("`expand` called on `MacroRulesMacroExpander`, expected `expand_with_safety`") + } + + fn expand_with_safety( + &self, cx: &mut ExtCtxt<'_>, + safety: Safety, sp: Span, args: TokenStream, body: TokenStream, @@ -260,6 +272,7 @@ impl AttrProcMacro for MacroRulesMacroExpander { self.node_id, self.name, self.transparency, + safety, args, body, &self.rules, @@ -267,16 +280,16 @@ impl AttrProcMacro for MacroRulesMacroExpander { } } -struct DummyExpander(ErrorGuaranteed); +struct DummyBang(ErrorGuaranteed); -impl TTMacroExpander for DummyExpander { +impl BangProcMacro for DummyBang { fn expand<'cx>( &self, _: &'cx mut ExtCtxt<'_>, - span: Span, + _: Span, _: TokenStream, - ) -> ExpandResult<Box<dyn MacResult + 'cx>, ()> { - ExpandResult::Ready(DummyResult::any(span, self.0)) + ) -> Result<TokenStream, ErrorGuaranteed> { + Err(self.0) } } @@ -408,6 +421,7 @@ fn expand_macro_attr( node_id: NodeId, name: Ident, transparency: Transparency, + safety: Safety, args: TokenStream, body: TokenStream, rules: &[MacroRule], @@ -429,13 +443,26 @@ fn expand_macro_attr( // Track nothing for the best performance. match try_match_macro_attr(psess, name, &args, &body, rules, &mut NoopTracker) { Ok((i, rule, named_matches)) => { - let MacroRule::Attr { rhs, .. } = rule else { + let MacroRule::Attr { rhs, unsafe_rule, .. } = rule else { panic!("try_macro_match_attr returned non-attr rule"); }; let mbe::TokenTree::Delimited(rhs_span, _, rhs) = rhs else { cx.dcx().span_bug(sp, "malformed macro rhs"); }; + match (safety, unsafe_rule) { + (Safety::Default, false) | (Safety::Unsafe(_), true) => {} + (Safety::Default, true) => { + cx.dcx().span_err(sp, "unsafe attribute invocation requires `unsafe`"); + } + (Safety::Unsafe(span), false) => { + cx.dcx().span_err(span, "unnecessary `unsafe` on safe attribute invocation"); + } + (Safety::Safe(span), _) => { + cx.dcx().span_bug(span, "unexpected `safe` keyword"); + } + } + let id = cx.current_expansion.id; let tts = transcribe(psess, &named_matches, rhs, *rhs_span, transparency, id) .map_err(|e| e.emit())?; @@ -664,7 +691,7 @@ pub fn compile_declarative_macro( SyntaxExtension::new(sess, kind, span, Vec::new(), edition, ident.name, attrs, is_local) }; let dummy_syn_ext = - |guar| (mk_syn_ext(SyntaxExtensionKind::LegacyBang(Arc::new(DummyExpander(guar)))), 0); + |guar| (mk_syn_ext(SyntaxExtensionKind::Bang(Arc::new(DummyBang(guar)))), 0); let macro_rules = macro_def.macro_rules; let exp_sep = if macro_rules { exp!(Semi) } else { exp!(Comma) }; @@ -681,6 +708,11 @@ pub fn compile_declarative_macro( let mut rules = Vec::new(); while p.token != token::Eof { + let unsafe_rule = p.eat_keyword_noexpect(kw::Unsafe); + let unsafe_keyword_span = p.prev_token.span; + if unsafe_rule && let Some(guar) = check_no_eof(sess, &p, "expected `attr`") { + return dummy_syn_ext(guar); + } let (args, is_derive) = if p.eat_keyword_noexpect(sym::attr) { kinds |= MacroKinds::ATTR; if !features.macro_attr() { @@ -705,6 +737,10 @@ pub fn compile_declarative_macro( feature_err(sess, sym::macro_derive, span, "`macro_rules!` derives are unstable") .emit(); } + if unsafe_rule { + sess.dcx() + .span_err(unsafe_keyword_span, "`unsafe` is only supported on `attr` rules"); + } if let Some(guar) = check_no_eof(sess, &p, "expected `()` after `derive`") { return dummy_syn_ext(guar); } @@ -730,6 +766,10 @@ pub fn compile_declarative_macro( (None, true) } else { kinds |= MacroKinds::BANG; + if unsafe_rule { + sess.dcx() + .span_err(unsafe_keyword_span, "`unsafe` is only supported on `attr` rules"); + } (None, false) }; let lhs_tt = p.parse_token_tree(); @@ -741,10 +781,10 @@ pub fn compile_declarative_macro( if let Some(guar) = check_no_eof(sess, &p, "expected right-hand side of macro rule") { return dummy_syn_ext(guar); } - let rhs_tt = p.parse_token_tree(); - let rhs_tt = parse_one_tt(rhs_tt, RulePart::Body, sess, node_id, features, edition); - check_emission(check_rhs(sess, &rhs_tt)); - check_emission(check_meta_variables(&sess.psess, node_id, args.as_ref(), &lhs_tt, &rhs_tt)); + let rhs = p.parse_token_tree(); + let rhs = parse_one_tt(rhs, RulePart::Body, sess, node_id, features, edition); + check_emission(check_rhs(sess, &rhs)); + check_emission(check_meta_variables(&sess.psess, node_id, args.as_ref(), &lhs_tt, &rhs)); let lhs_span = lhs_tt.span(); // Convert the lhs into `MatcherLoc` form, which is better for doing the // actual matching. @@ -760,11 +800,11 @@ pub fn compile_declarative_macro( }; let args = mbe::macro_parser::compute_locs(&delimited.tts); let body_span = lhs_span; - rules.push(MacroRule::Attr { args, args_span, body: lhs, body_span, rhs: rhs_tt }); + rules.push(MacroRule::Attr { unsafe_rule, args, args_span, body: lhs, body_span, rhs }); } else if is_derive { - rules.push(MacroRule::Derive { body: lhs, body_span: lhs_span, rhs: rhs_tt }); + rules.push(MacroRule::Derive { body: lhs, body_span: lhs_span, rhs }); } else { - rules.push(MacroRule::Func { lhs, lhs_span, rhs: rhs_tt }); + rules.push(MacroRule::Func { lhs, lhs_span, rhs }); } if p.token == token::Eof { break; @@ -894,12 +934,12 @@ fn check_redundant_vis_repetition( seq: &SequenceRepetition, span: &DelimSpan, ) { - let is_zero_or_one: bool = seq.kleene.op == KleeneOp::ZeroOrOne; - let is_vis = seq.tts.first().map_or(false, |tt| { - matches!(tt, mbe::TokenTree::MetaVarDecl { kind: NonterminalKind::Vis, .. }) - }); - - if is_vis && is_zero_or_one { + if seq.kleene.op == KleeneOp::ZeroOrOne + && matches!( + seq.tts.first(), + Some(mbe::TokenTree::MetaVarDecl { kind: NonterminalKind::Vis, .. }) + ) + { err.note("a `vis` fragment can already be empty"); err.multipart_suggestion( "remove the `$(` and `)?`", |