rustdoc,metadata: Debugging

src/librustc_metadata/creader.rs

@@ -222,6 +222,7 @@ fn existing_match(&self, name: Symbol, hash: Option<Svh>, kind: PathKind) -> Opt
         let mut ret = None;
         self.cstore.iter_crate_data(|cnum, data| {
             if data.name() != name {
+                tracing::trace!("{} did not match {}", data.name(), name);
                 return;
             }
 
@@ -230,7 +231,10 @@ fn existing_match(&self, name: Symbol, hash: Option<Svh>, kind: PathKind) -> Opt
                     ret = Some(cnum);
                     return;
                 }
-                Some(..) => return,
+                Some(hash) => {
+                    debug!("actual hash {} did not match expected {}", hash, data.hash());
+                    return;
+                }
                 None => {}
             }
 
@@ -273,6 +277,11 @@ fn existing_match(&self, name: Symbol, hash: Option<Svh>, kind: PathKind) -> Opt
                 .1;
             if kind.matches(prev_kind) {
                 ret = Some(cnum);
+            } else {
+                debug!(
+                    "failed to load existing crate {}; kind {:?} did not match prev_kind {:?}",
+                    name, kind, prev_kind
+                );
             }
         });
         ret

src/librustdoc/core.rs

@@ -439,6 +439,7 @@ pub fn run_core(
                 resolver.borrow_mut().access(|resolver| {
                     sess.time("load_extern_crates", || {
                         for extern_name in &extern_names {
+                            debug!("loading extern crate {}", extern_name);
                             resolver
                                 .resolve_str_path_error(
                                     DUMMY_SP,

src/librustdoc/passes/collect_intra_doc_links.rs

@@ -161,6 +161,7 @@ fn macro_resolve(&self, path_str: &str, parent_id: Option<DefId>) -> Option<Res>
                 return Some(res.map_id(|_| panic!("unexpected id")));
             }
             if let Some(module_id) = parent_id {
+                debug!("resolving {} as a macro in the module {:?}", path_str, module_id);
                 if let Ok((_, res)) =
                     resolver.resolve_str_path_error(DUMMY_SP, path_str, MacroNS, module_id)
                 {