rustc_metadata: Load metadata for indirect macro-only dependencies

Author: petrochenkov

src/librustc/middle/cstore.rs

@@ -53,9 +53,6 @@ impl CrateSource {
     HashStable
 )]
 pub enum DepKind {
-    /// A dependency that is only used for its macros, none of which are visible from other crates.
-    /// These are included in the metadata only as placeholders and are ignored when decoding.
-    UnexportedMacrosOnly,
     /// A dependency that is only used for its macros.
     MacrosOnly,
     /// A dependency that is always injected into the dependency list and so
@@ -69,7 +66,7 @@ pub enum DepKind {
 impl DepKind {
     pub fn macros_only(self) -> bool {
         match self {
-            DepKind::UnexportedMacrosOnly | DepKind::MacrosOnly => true,
+            DepKind::MacrosOnly => true,
             DepKind::Implicit | DepKind::Explicit => false,
         }
     }

src/librustc_metadata/creader.rs

@@ -463,7 +463,7 @@ impl<'a> CrateLoader<'a> {
             self.load(&mut locator)
                 .map(|r| (r, None))
                 .or_else(|| {
-                    dep_kind = DepKind::UnexportedMacrosOnly;
+                    dep_kind = DepKind::MacrosOnly;
                     self.load_proc_macro(&mut locator, path_kind)
                 })
                 .ok_or_else(move || LoadError::LocatorError(locator))?
@@ -473,7 +473,7 @@ impl<'a> CrateLoader<'a> {
             (LoadResult::Previous(cnum), None) => {
                 let data = self.cstore.get_crate_data(cnum);
                 if data.is_proc_macro_crate() {
-                    dep_kind = DepKind::UnexportedMacrosOnly;
+                    dep_kind = DepKind::MacrosOnly;
                 }
                 data.update_dep_kind(|data_dep_kind| cmp::max(data_dep_kind, dep_kind));
                 Ok(cnum)
@@ -547,9 +547,6 @@ impl<'a> CrateLoader<'a> {
                     "resolving dep crate {} hash: `{}` extra filename: `{}`",
                     dep.name, dep.hash, dep.extra_filename
                 );
-                if dep.kind == DepKind::UnexportedMacrosOnly {
-                    return krate;
-                }
                 let dep_kind = match dep_kind {
                     DepKind::MacrosOnly => DepKind::MacrosOnly,
                     _ => dep.kind,
@@ -853,7 +850,7 @@ impl<'a> CrateLoader<'a> {
                     None => item.ident.name,
                 };
                 let dep_kind = if attr::contains_name(&item.attrs, sym::no_link) {
-                    DepKind::UnexportedMacrosOnly
+                    DepKind::MacrosOnly
                 } else {
                     DepKind::Explicit
                 };

src/librustc_metadata/rmeta/decoder/cstore_impl.rs

@@ -7,7 +7,7 @@ use crate::rmeta::{self, encoder};
 use rustc::hir::exports::Export;
 use rustc::hir::map::definitions::DefPathTable;
 use rustc::hir::map::{DefKey, DefPath, DefPathHash};
-use rustc::middle::cstore::{CrateSource, CrateStore, DepKind, EncodedMetadata, NativeLibraryKind};
+use rustc::middle::cstore::{CrateSource, CrateStore, EncodedMetadata, NativeLibraryKind};
 use rustc::middle::exported_symbols::ExportedSymbol;
 use rustc::middle::stability::DeprecationEntry;
 use rustc::session::{CrateDisambiguator, Session};
@@ -392,14 +392,6 @@ pub fn provide(providers: &mut Providers<'_>) {
 }
 
 impl CStore {
-    pub fn export_macros_untracked(&self, cnum: CrateNum) {
-        let data = self.get_crate_data(cnum);
-        let mut dep_kind = data.dep_kind.lock();
-        if *dep_kind == DepKind::UnexportedMacrosOnly {
-            *dep_kind = DepKind::MacrosOnly;
-        }
-    }
-
     pub fn struct_field_names_untracked(&self, def: DefId, sess: &Session) -> Vec<Spanned<Symbol>> {
         self.get_crate_data(def.krate).get_struct_field_names(def.index, sess)
     }

src/librustc_resolve/imports.rs

@@ -1403,11 +1403,6 @@ impl<'a, 'b> ImportResolver<'a, 'b> {
             if is_good_import || binding.is_macro_def() {
                 let res = binding.res();
                 if res != Res::Err {
-                    if let Some(def_id) = res.opt_def_id() {
-                        if !def_id.is_local() {
-                            this.cstore().export_macros_untracked(def_id.krate);
-                        }
-                    }
                     reexports.push(Export { ident, res, span: binding.span, vis: binding.vis });
                 }
             }