Move syntax_expand::config to rustc_parse::config

src/librustc_parse/config.rs

@@ -1,4 +1,14 @@
-use rustc_parse::validate_attr;
+//! Process the potential `cfg` attributes on a module.
+//! Also determine if the module should be included in this configuration.
+//!
+//! This module properly belongs in syntax_expand, but for now it's tied into
+//! parsing, so we leave it here to avoid complicated out-of-line dependencies.
+//!
+//! A principled solution to this wrong location would be to implement [#64197].
+//!
+//! [#64197]: https://github.com/rust-lang/rust/issues/64197
+
+use crate::validate_attr;
 use syntax::attr::HasAttrs;
 use syntax::feature_gate::{
     feature_err,
@@ -113,7 +123,7 @@ impl<'a> StripUnconfigured<'a> {
             return vec![];
         }
 
-        let res = rustc_parse::parse_in_attr(self.sess, &attr, |p| p.parse_cfg_attr());
+        let res = crate::parse_in_attr(self.sess, &attr, |p| p.parse_cfg_attr());
         let (cfg_predicate, expanded_attrs) = match res {
             Ok(result) => result,
             Err(mut e) => {

src/librustc_parse/lib.rs

@@ -25,6 +25,8 @@ pub mod parser;
 use parser::{Parser, emit_unclosed_delims, make_unclosed_delims_error};
 pub mod lexer;
 pub mod validate_attr;
+#[macro_use]
+pub mod config;
 
 #[derive(Clone)]
 pub struct Directory<'a> {

src/librustc_parse/parser/module.rs

@@ -41,7 +41,7 @@ impl<'a> Parser<'a> {
     /// Parses a `mod <foo> { ... }` or `mod <foo>;` item.
     pub(super) fn parse_item_mod(&mut self, outer_attrs: &[Attribute]) -> PResult<'a, ItemInfo> {
         // HACK(Centril): See documentation on `ParseSess::process_cfg_mod`.
-        let (in_cfg, outer_attrs) = (self.sess.process_cfg_mod)(
+        let (in_cfg, outer_attrs) = crate::config::process_configure_mod(
             self.sess,
             self.cfg_mods,
             outer_attrs,

src/libsyntax_expand/expand.rs

@@ -4,7 +4,7 @@ use crate::hygiene::{ExpnId, SyntaxContext, ExpnData, ExpnKind};
 use crate::mbe::macro_rules::annotate_err_with_kind;
 use crate::placeholders::{placeholder, PlaceholderExpander};
 use crate::config::StripUnconfigured;
-use crate::configure;
+use rustc_parse::configure;
 
 use rustc_parse::DirectoryOwnership;
 use rustc_parse::parser::Parser;

src/libsyntax_expand/lib.rs

@@ -33,7 +33,7 @@ pub use mbe::macro_rules::compile_declarative_macro;
 pub mod base;
 pub mod build;
 pub mod expand;
-#[macro_use] pub mod config;
+pub use rustc_parse::config;
 pub mod proc_macro;
 
 crate mod mbe;