rustc_metadata: Crate loader is immutable

src/librustc_interface/passes.rs

@@ -130,7 +130,7 @@ pub fn configure_and_expand(
     let crate_name = crate_name.to_string();
     let (result, resolver) = BoxedResolver::new(static move || {
         let sess = &*sess;
-        let mut crate_loader = CrateLoader::new(sess, &*cstore, &crate_name);
+        let crate_loader = CrateLoader::new(sess, &*cstore, &crate_name);
         let resolver_arenas = Resolver::arenas();
         let res = configure_and_expand_inner(
             sess,
@@ -138,7 +138,7 @@ pub fn configure_and_expand(
             krate,
             &crate_name,
             &resolver_arenas,
-            &mut crate_loader,
+            &crate_loader,
             plugin_info,
         );
         let mut resolver = match res {
@@ -319,7 +319,7 @@ fn configure_and_expand_inner<'a>(
     mut krate: ast::Crate,
     crate_name: &str,
     resolver_arenas: &'a ResolverArenas<'a>,
-    crate_loader: &'a mut CrateLoader<'a>,
+    crate_loader: &'a CrateLoader<'a>,
     plugin_info: PluginInfo,
 ) -> Result<(ast::Crate, Resolver<'a>)> {
     time(sess, "pre-AST-expansion lint checks", || {

src/librustc_metadata/creader.rs

@@ -187,7 +187,7 @@ impl<'a> CrateLoader<'a> {
     }
 
     fn register_crate(
-        &mut self,
+        &self,
         host_lib: Option<Library>,
         root: Option<&CratePaths>,
         span: Span,
@@ -272,7 +272,7 @@ impl<'a> CrateLoader<'a> {
     }
 
     fn load_proc_macro<'b>(
-        &mut self,
+        &self,
         locate_ctxt: &mut locator::Context<'b>,
         path_kind: PathKind,
     ) -> Option<(LoadResult, Option<Library>)>
@@ -327,7 +327,7 @@ impl<'a> CrateLoader<'a> {
     }
 
     fn resolve_crate<'b>(
-        &'b mut self,
+        &'b self,
         name: Symbol,
         span: Span,
         dep_kind: DepKind,
@@ -337,7 +337,7 @@ impl<'a> CrateLoader<'a> {
     }
 
     fn maybe_resolve_crate<'b>(
-        &'b mut self,
+        &'b self,
         name: Symbol,
         span: Span,
         mut dep_kind: DepKind,
@@ -397,7 +397,7 @@ impl<'a> CrateLoader<'a> {
         }
     }
 
-    fn load(&mut self, locate_ctxt: &mut locator::Context<'_>) -> Option<LoadResult> {
+    fn load(&self, locate_ctxt: &mut locator::Context<'_>) -> Option<LoadResult> {
         let library = locate_ctxt.maybe_load_library_crate()?;
 
         // In the case that we're loading a crate, but not matching
@@ -424,7 +424,7 @@ impl<'a> CrateLoader<'a> {
         }
     }
 
-    fn update_extern_crate(&mut self,
+    fn update_extern_crate(&self,
                            cnum: CrateNum,
                            mut extern_crate: ExternCrate,
                            visited: &mut FxHashSet<(CrateNum, bool)>)
@@ -466,7 +466,7 @@ impl<'a> CrateLoader<'a> {
     }
 
     // Go through the crate metadata and load any crates that it references
-    fn resolve_crate_deps(&mut self,
+    fn resolve_crate_deps(&self,
                           root: &CratePaths,
                           crate_root: &CrateRoot<'_>,
                           metadata: &MetadataBlob,
@@ -496,7 +496,7 @@ impl<'a> CrateLoader<'a> {
         })).collect()
     }
 
-    fn read_extension_crate(&mut self, name: Symbol, span: Span) -> ExtensionCrate {
+    fn read_extension_crate(&self, name: Symbol, span: Span) -> ExtensionCrate {
         info!("read extension crate `{}`", name);
         let target_triple = self.sess.opts.target_triple.clone();
         let host_triple = TargetTriple::from_triple(config::host_triple());
@@ -592,7 +592,7 @@ impl<'a> CrateLoader<'a> {
 
     /// Look for a plugin registrar. Returns library path, crate
     /// SVH and DefIndex of the registrar function.
-    pub fn find_plugin_registrar(&mut self,
+    pub fn find_plugin_registrar(&self,
                                  span: Span,
                                  name: Symbol)
                                  -> Option<(PathBuf, CrateDisambiguator)> {
@@ -625,7 +625,7 @@ impl<'a> CrateLoader<'a> {
         }
     }
 
-    fn inject_panic_runtime(&mut self, krate: &ast::Crate) {
+    fn inject_panic_runtime(&self, krate: &ast::Crate) {
         // If we're only compiling an rlib, then there's no need to select a
         // panic runtime, so we just skip this section entirely.
         let any_non_rlib = self.sess.crate_types.borrow().iter().any(|ct| {
@@ -706,7 +706,7 @@ impl<'a> CrateLoader<'a> {
                                   &|data| data.root.needs_panic_runtime);
     }
 
-    fn inject_sanitizer_runtime(&mut self) {
+    fn inject_sanitizer_runtime(&self) {
         if let Some(ref sanitizer) = self.sess.opts.debugging_opts.sanitizer {
             // Sanitizers can only be used on some tested platforms with
             // executables linked to `std`
@@ -804,7 +804,7 @@ impl<'a> CrateLoader<'a> {
         }
     }
 
-    fn inject_profiler_runtime(&mut self) {
+    fn inject_profiler_runtime(&self) {
         if self.sess.opts.debugging_opts.profile ||
            self.sess.opts.cg.profile_generate.enabled()
         {
@@ -821,7 +821,7 @@ impl<'a> CrateLoader<'a> {
         }
     }
 
-    fn inject_allocator_crate(&mut self, krate: &ast::Crate) {
+    fn inject_allocator_crate(&self, krate: &ast::Crate) {
         let has_global_allocator = match &*global_allocator_spans(krate) {
             [span1, span2, ..] => {
                 self.sess.struct_span_err(*span2, "cannot define multiple global allocators")
@@ -960,7 +960,7 @@ impl<'a> CrateLoader<'a> {
 }
 
 impl<'a> CrateLoader<'a> {
-    pub fn postprocess(&mut self, krate: &ast::Crate) {
+    pub fn postprocess(&self, krate: &ast::Crate) {
         self.inject_sanitizer_runtime();
         self.inject_profiler_runtime();
         self.inject_allocator_crate(krate);
@@ -971,9 +971,7 @@ impl<'a> CrateLoader<'a> {
         }
     }
 
-    pub fn process_extern_crate(
-        &mut self, item: &ast::Item, definitions: &Definitions,
-    ) -> CrateNum {
+    pub fn process_extern_crate(&self, item: &ast::Item, definitions: &Definitions) -> CrateNum {
         match item.kind {
             ast::ItemKind::ExternCrate(orig_name) => {
                 debug!("resolving extern crate stmt. ident: {} orig_name: {:?}",
@@ -1013,11 +1011,7 @@ impl<'a> CrateLoader<'a> {
         }
     }
 
-    pub fn process_path_extern(
-        &mut self,
-        name: Symbol,
-        span: Span,
-    ) -> CrateNum {
+    pub fn process_path_extern(&self, name: Symbol, span: Span) -> CrateNum {
         let cnum = self.resolve_crate(name, span, DepKind::Explicit, None).0;
 
         self.update_extern_crate(
@@ -1035,11 +1029,7 @@ impl<'a> CrateLoader<'a> {
         cnum
     }
 
-    pub fn maybe_process_path_extern(
-        &mut self,
-        name: Symbol,
-        span: Span,
-    ) -> Option<CrateNum> {
+    pub fn maybe_process_path_extern(&self, name: Symbol, span: Span) -> Option<CrateNum> {
         let cnum = self.maybe_resolve_crate(name, span, DepKind::Explicit, None).ok()?.0;
 
         self.update_extern_crate(

src/librustc_resolve/lib.rs

@@ -900,7 +900,7 @@ pub struct Resolver<'a> {
     arenas: &'a ResolverArenas<'a>,
     dummy_binding: &'a NameBinding<'a>,
 
-    crate_loader: &'a mut CrateLoader<'a>,
+    crate_loader: &'a CrateLoader<'a>,
     macro_names: FxHashSet<Ident>,
     builtin_macros: FxHashMap<Name, SyntaxExtension>,
     macro_use_prelude: FxHashMap<Name, &'a NameBinding<'a>>,
@@ -1070,7 +1070,7 @@ impl<'a> Resolver<'a> {
                cstore: &'a CStore,
                krate: &Crate,
                crate_name: &str,
-               crate_loader: &'a mut CrateLoader<'a>,
+               crate_loader: &'a CrateLoader<'a>,
                arenas: &'a ResolverArenas<'a>)
                -> Resolver<'a> {
         let root_def_id = DefId::local(CRATE_DEF_INDEX);