Port #[cfg] to the new attribute parsing infrastructure

Signed-off-by: Jonathan Brouwer <[email protected]>

Author: JonathanBrouwer

compiler/rustc_ast/src/expand/mod.rs

@@ -1,24 +1,7 @@
 //! Definitions shared by macros / syntax extensions and e.g. `rustc_middle`.
 
 use rustc_macros::{Decodable, Encodable, HashStable_Generic};
-use rustc_span::Ident;
-use rustc_span::def_id::DefId;
-
-use crate::MetaItem;
 
 pub mod allocator;
 pub mod autodiff_attrs;
 pub mod typetree;
-
-#[derive(Debug, Clone, Encodable, Decodable, HashStable_Generic)]
-pub struct StrippedCfgItem<ModId = DefId> {
-    pub parent_module: ModId,
-    pub ident: Ident,
-    pub cfg: MetaItem,
-}
-
-impl<ModId> StrippedCfgItem<ModId> {
-    pub fn map_mod_id<New>(self, f: impl FnOnce(ModId) -> New) -> StrippedCfgItem<New> {
-        StrippedCfgItem { parent_module: f(self.parent_module), ident: self.ident, cfg: self.cfg }
-    }
-}

compiler/rustc_attr_data_structures/src/attributes.rs

@@ -3,7 +3,7 @@ use rustc_ast::token::CommentKind;
 use rustc_ast::{self as ast, AttrStyle};
 use rustc_macros::{Decodable, Encodable, HashStable_Generic, PrintAttribute};
 use rustc_span::hygiene::Transparency;
-use rustc_span::{Span, Symbol};
+use rustc_span::{Ident, Span, Symbol};
 use thin_vec::ThinVec;
 
 use crate::{DefaultBodyStability, PartialConstStability, PrintAttribute, RustcVersion, Stability};
@@ -69,6 +69,7 @@ pub enum ReprAttr {
     ReprAlign(Align),
 }
 pub use ReprAttr::*;
+use rustc_span::def_id::DefId;
 
 pub enum TransparencyError {
     UnknownTransparency(Symbol, Span),
@@ -140,6 +141,29 @@ pub enum UsedBy {
     Linker,
 }
 
+#[derive(Debug, Clone, Encodable, Decodable, HashStable_Generic)]
+pub struct StrippedCfgItem<ModId = DefId> {
+    pub parent_module: ModId,
+    pub ident: Ident,
+    pub cfg: (CfgEntry, Span),
+}
+
+impl<ModId> StrippedCfgItem<ModId> {
+    pub fn map_mod_id<New>(self, f: impl FnOnce(ModId) -> New) -> StrippedCfgItem<New> {
+        StrippedCfgItem { parent_module: f(self.parent_module), ident: self.ident, cfg: self.cfg }
+    }
+}
+
+#[derive(Encodable, Decodable, Clone, Debug, PartialEq, Eq, Hash)]
+#[derive(HashStable_Generic, PrintAttribute)]
+pub enum CfgEntry {
+    All(ThinVec<CfgEntry>, Span),
+    Any(ThinVec<CfgEntry>, Span),
+    Not(Box<CfgEntry>, Span),
+    Bool(bool, Span),
+    NameValue { name: Symbol, name_span: Span, value: Option<(Symbol, Span)>, span: Span },
+}
+
 /// Represents parsed *built-in* inert attributes.
 ///
 /// ## Overview
@@ -211,6 +235,9 @@ pub enum AttributeKind {
         span: Span,
     },
 
+    /// Represents `#[cfg]`.
+    Cfg(CfgEntry, Span),
+
     /// Represents `#[cold]`.
     Cold(Span),
 

compiler/rustc_attr_data_structures/src/encode_cross_crate.rs

@@ -17,6 +17,7 @@ impl AttributeKind {
             AllowInternalUnstable(..) => Yes,
             AsPtr(..) => Yes,
             BodyStability { .. } => No,
+            Cfg(..) => Yes,
             Confusables { .. } => Yes,
             ConstStability { .. } => Yes,
             ConstStabilityIndirect => No,

compiler/rustc_attr_parsing/src/attributes/cfg.rs

@@ -74,7 +74,7 @@ pub fn cfg_matches(
     })
 }
 
-fn try_gate_cfg(name: Symbol, span: Span, sess: &Session, features: Option<&Features>) {
+pub fn try_gate_cfg(name: Symbol, span: Span, sess: &Session, features: Option<&Features>) {
     let gate = find_gated_cfg(|sym| sym == name);
     if let (Some(feats), Some(gated_cfg)) = (features, gate) {
         gate_cfg(gated_cfg, span, sess, feats);