Auto merge of #88538 - bjorn3:no_session_in_crate_loader, r=petrochenkov

CrateLocator refactorings

This makes the `CrateLocator` a lot cleaner IMHO and much more self-contained. The last commit removes `extra_filename` from the crate metadata. This is an **insta-stable** change as it allows a crate like `libfoo-abc.rlib` to be used as dependency and then be renamed as `libfoo-bcd.rlib` while still being found as indirect dependency. This may reduce performance when there are a lot of versions of the same crate available as the extra filename won't be used to do an early rejection of crates before trying to load metadata, but it makes the logic to find the right filename a lot cleaner.

compiler/rustc_metadata/src/creader.rs

@@ -450,6 +450,7 @@ impl<'a> CrateLoader<'a> {
         &self,
         locator: &mut CrateLocator<'b>,
         path_kind: PathKind,
+        host_hash: Option<Svh>,
     ) -> Result<Option<(LoadResult, Option<Library>)>, CrateError>
     where
         'a: 'b,
@@ -459,7 +460,7 @@ impl<'a> CrateLoader<'a> {
         let mut proc_macro_locator = locator.clone();
 
         // Try to load a proc macro
-        proc_macro_locator.is_proc_macro = Some(true);
+        proc_macro_locator.is_proc_macro = true;
 
         // Load the proc macro crate for the target
         let (locator, target_result) = if self.sess.opts.debugging_opts.dual_proc_macros {
@@ -471,7 +472,7 @@ impl<'a> CrateLoader<'a> {
                 Some(LoadResult::Loaded(library)) => Some(LoadResult::Loaded(library)),
                 None => return Ok(None),
             };
-            locator.hash = locator.host_hash;
+            locator.hash = host_hash;
             // Use the locator when looking for the host proc macro crate, as that is required
             // so we want it to affect the error message
             (locator, result)
@@ -482,7 +483,7 @@ impl<'a> CrateLoader<'a> {
         // Load the proc macro crate for the host
 
         locator.reset();
-        locator.is_proc_macro = Some(true);
+        locator.is_proc_macro = true;
         locator.target = &self.sess.host;
         locator.triple = TargetTriple::from_triple(config::host_triple());
         locator.filesearch = self.sess.host_filesearch(path_kind);
@@ -510,12 +511,9 @@ impl<'a> CrateLoader<'a> {
         name: Symbol,
         span: Span,
         dep_kind: CrateDepKind,
-        dep: Option<(&'b CratePaths, &'b CrateDep)>,
     ) -> CrateNum {
-        if dep.is_none() {
-            self.used_extern_options.insert(name);
-        }
-        self.maybe_resolve_crate(name, dep_kind, dep).unwrap_or_else(|err| {
+        self.used_extern_options.insert(name);
+        self.maybe_resolve_crate(name, dep_kind, None).unwrap_or_else(|err| {
             let missing_core =
                 self.maybe_resolve_crate(sym::core, CrateDepKind::Explicit, None).is_err();
             err.report(&self.sess, span, missing_core)
@@ -551,21 +549,18 @@ impl<'a> CrateLoader<'a> {
                 &*self.metadata_loader,
                 name,
                 hash,
-                host_hash,
                 extra_filename,
                 false, // is_host
                 path_kind,
-                root,
-                Some(false), // is_proc_macro
             );
 
             match self.load(&mut locator)? {
                 Some(res) => (res, None),
                 None => {
                     dep_kind = CrateDepKind::MacrosOnly;
-                    match self.load_proc_macro(&mut locator, path_kind)? {
+                    match self.load_proc_macro(&mut locator, path_kind, host_hash)? {
                         Some(res) => res,
-                        None => return Err(locator.into_error()),
+                        None => return Err(locator.into_error(root.cloned())),
                     }
                 }
             }
@@ -605,7 +600,7 @@ impl<'a> CrateLoader<'a> {
         // FIXME: why is this condition necessary? It was adding in #33625 but I
         // don't know why and the original author doesn't remember ...
         let can_reuse_cratenum =
-            locator.triple == self.sess.opts.target_triple || locator.is_proc_macro == Some(true);
+            locator.triple == self.sess.opts.target_triple || locator.is_proc_macro;
         Ok(Some(if can_reuse_cratenum {
             let mut result = LoadResult::Loaded(library);
             self.cstore.iter_crate_data(|cnum, data| {
@@ -755,7 +750,7 @@ impl<'a> CrateLoader<'a> {
         };
         info!("panic runtime not found -- loading {}", name);
 
-        let cnum = self.resolve_crate(name, DUMMY_SP, CrateDepKind::Implicit, None);
+        let cnum = self.resolve_crate(name, DUMMY_SP, CrateDepKind::Implicit);
         let data = self.cstore.get_crate_data(cnum);
 
         // Sanity check the loaded crate to ensure it is indeed a panic runtime
@@ -795,7 +790,7 @@ impl<'a> CrateLoader<'a> {
             );
         }
 
-        let cnum = self.resolve_crate(name, DUMMY_SP, CrateDepKind::Implicit, None);
+        let cnum = self.resolve_crate(name, DUMMY_SP, CrateDepKind::Implicit);
         let data = self.cstore.get_crate_data(cnum);
 
         // Sanity check the loaded crate to ensure it is indeed a profiler runtime
@@ -1015,7 +1010,7 @@ impl<'a> CrateLoader<'a> {
                     CrateDepKind::Explicit
                 };
 
-                let cnum = self.resolve_crate(name, item.span, dep_kind, None);
+                let cnum = self.resolve_crate(name, item.span, dep_kind);
 
                 let path_len = definitions.def_path(def_id).data.len();
                 self.update_extern_crate(
@@ -1034,7 +1029,7 @@ impl<'a> CrateLoader<'a> {
     }
 
     pub fn process_path_extern(&mut self, name: Symbol, span: Span) -> CrateNum {
-        let cnum = self.resolve_crate(name, span, CrateDepKind::Explicit, None);
+        let cnum = self.resolve_crate(name, span, CrateDepKind::Explicit);
 
         self.update_extern_crate(
             cnum,