Auto merge of #57607 - Centril:rollup, r=Centril

Rollup of 8 pull requests

Successful merges:

 - #57043 (Fix poor worst case performance of set intersection)
 - #57480 (Clean up and fix a bug in query plumbing)
 - #57481 (provide suggestion for invalid boolean cast)
 - #57540 (Modify some parser diagnostics to continue evaluating beyond the parser)
 - #57570 (Querify local `plugin_registrar_fn` and `proc_macro_decls_static`)
 - #57572 (Unaccept `extern_in_paths`)
 - #57585 (Recover from item trailing semicolon)
 - #57589 (Add a debug_assert to Vec::set_len)

Failed merges:

r? @ghost

Author: bors

src/doc/unstable-book/src/language-features/extern-in-paths.md

@@ -819,6 +819,8 @@ impl<T> Vec<T> {
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub unsafe fn set_len(&mut self, new_len: usize) {
+        debug_assert!(new_len <= self.capacity());
+
         self.len = new_len;
     }
 

src/liballoc/vec.rs

@@ -140,7 +140,7 @@ pub enum ExternCrateSource {
     ),
     // Crate is loaded by `use`.
     Use,
-    /// Crate is implicitly loaded by an absolute or an `extern::` path.
+    /// Crate is implicitly loaded by an absolute path.
     Path,
 }
 

src/librustc/middle/cstore.rs

@@ -69,8 +69,6 @@ pub struct Session {
     pub parse_sess: ParseSess,
     /// For a library crate, this is always none
     pub entry_fn: Once<Option<(NodeId, Span, config::EntryFnType)>>,
-    pub plugin_registrar_fn: Once<Option<ast::NodeId>>,
-    pub proc_macro_decls_static: Once<Option<ast::NodeId>>,
     pub sysroot: PathBuf,
     /// The name of the root source file of the crate, in the local file system.
     /// `None` means that there is no source file.
@@ -1177,8 +1175,6 @@ pub fn build_session_(
         parse_sess: p_s,
         // For a library crate, this is always none
         entry_fn: Once::new(),
-        plugin_registrar_fn: Once::new(),
-        proc_macro_decls_static: Once::new(),
         sysroot,
         local_crate_source_file,
         working_dir,

src/librustc/session/mod.rs

@@ -402,7 +402,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         // expensive for some DepKinds.
         if !self.dep_graph.is_fully_enabled() {
             let null_dep_node = DepNode::new_no_params(::dep_graph::DepKind::Null);
-            return self.force_query_with_job::<Q>(key, job, null_dep_node).map(|(v, _)| v);
+            return Ok(self.force_query_with_job::<Q>(key, job, null_dep_node).0);
         }
 
         let dep_node = Q::to_dep_node(self, &key);
@@ -436,20 +436,18 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
 
         if !dep_node.kind.is_input() {
             if let Some(dep_node_index) = self.try_mark_green_and_read(&dep_node) {
-                return self.load_from_disk_and_cache_in_memory::<Q>(key,
-                                                                    job,
-                                                                    dep_node_index,
-                                                                    &dep_node)
+                return Ok(self.load_from_disk_and_cache_in_memory::<Q>(
+                    key,
+                    job,
+                    dep_node_index,
+                    &dep_node
+                ))
             }
         }
 
-        match self.force_query_with_job::<Q>(key, job, dep_node) {
-            Ok((result, dep_node_index)) => {
-                self.dep_graph.read_index(dep_node_index);
-                Ok(result)
-            }
-            Err(e) => Err(e)
-        }
+        let (result, dep_node_index) = self.force_query_with_job::<Q>(key, job, dep_node);
+        self.dep_graph.read_index(dep_node_index);
+        Ok(result)
     }
 
     fn load_from_disk_and_cache_in_memory<Q: QueryDescription<'gcx>>(
@@ -458,7 +456,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         job: JobOwner<'a, 'gcx, Q>,
         dep_node_index: DepNodeIndex,
         dep_node: &DepNode
-    ) -> Result<Q::Value, Box<CycleError<'gcx>>>
+    ) -> Q::Value
     {
         // Note this function can be called concurrently from the same query
         // We must ensure that this is handled correctly
@@ -523,7 +521,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
 
         job.complete(&result, dep_node_index);
 
-        Ok(result)
+        result
     }
 
     #[inline(never)]
@@ -563,7 +561,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         key: Q::Key,
         job: JobOwner<'_, 'gcx, Q>,
         dep_node: DepNode)
-    -> Result<(Q::Value, DepNodeIndex), Box<CycleError<'gcx>>> {
+    -> (Q::Value, DepNodeIndex) {
         // If the following assertion triggers, it can have two reasons:
         // 1. Something is wrong with DepNode creation, either here or
         //    in DepGraph::try_mark_green()
@@ -610,7 +608,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
 
         job.complete(&result, dep_node_index);
 
-        Ok((result, dep_node_index))
+        (result, dep_node_index)
     }
 
     /// Ensure that either this query has all green inputs or been executed.
@@ -657,11 +655,14 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         // Ensure that only one of them runs the query
         let job = match JobOwner::try_get(self, span, &key) {
             TryGetJob::NotYetStarted(job) => job,
-            TryGetJob::JobCompleted(_) => return,
+            TryGetJob::JobCompleted(result) => {
+                if let Err(e) = result {
+                    self.report_cycle(e).emit();
+                }
+                return
+            }
         };
-        if let Err(e) = self.force_query_with_job::<Q>(key, job, dep_node) {
-            self.report_cycle(e).emit();
-        }
+        self.force_query_with_job::<Q>(key, job, dep_node);
     }
 
     pub(super) fn try_get_query<Q: QueryDescription<'gcx>>(

src/librustc/ty/query/plumbing.rs

@@ -147,14 +147,12 @@ fn reachable_non_generics_provider<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         })
         .collect();
 
-    if let Some(id) = *tcx.sess.proc_macro_decls_static.get() {
-        let def_id = tcx.hir().local_def_id(id);
-        reachable_non_generics.insert(def_id, SymbolExportLevel::C);
+    if let Some(id) = tcx.proc_macro_decls_static(LOCAL_CRATE) {
+        reachable_non_generics.insert(id, SymbolExportLevel::C);
     }
 
-    if let Some(id) = *tcx.sess.plugin_registrar_fn.get() {
-        let def_id = tcx.hir().local_def_id(id);
-        reachable_non_generics.insert(def_id, SymbolExportLevel::C);
+    if let Some(id) = tcx.plugin_registrar_fn(LOCAL_CRATE) {
+        reachable_non_generics.insert(id, SymbolExportLevel::C);
     }
 
     Lrc::new(reachable_non_generics)

src/librustc_codegen_ssa/back/symbol_export.rs

@@ -242,12 +242,12 @@ fn compute_symbol_name<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, instance: Instance
 
     let node_id = tcx.hir().as_local_node_id(def_id);
 
-    if let Some(id) = node_id {
-        if *tcx.sess.plugin_registrar_fn.get() == Some(id) {
+    if def_id.is_local() {
+        if tcx.plugin_registrar_fn(LOCAL_CRATE) == Some(def_id) {
             let disambiguator = tcx.sess.local_crate_disambiguator();
             return tcx.sess.generate_plugin_registrar_symbol(disambiguator);
         }
-        if *tcx.sess.proc_macro_decls_static.get() == Some(id) {
+        if tcx.proc_macro_decls_static(LOCAL_CRATE) == Some(def_id) {
             let disambiguator = tcx.sess.local_crate_disambiguator();
             return tcx.sess.generate_proc_macro_decls_symbol(disambiguator);
         }

src/librustc_codegen_utils/symbol_names.rs

@@ -1158,6 +1158,8 @@ where
 }
 
 pub fn default_provide(providers: &mut ty::query::Providers) {
+    proc_macro_decls::provide(providers);
+    plugin::build::provide(providers);
     hir::provide(providers);
     borrowck::provide(providers);
     mir::provide(providers);
@@ -1212,13 +1214,6 @@ where
         middle::entry::find_entry_point(sess, &hir_map, name)
     });
 
-    sess.plugin_registrar_fn
-        .set(time(sess, "looking for plugin registrar", || {
-            plugin::build::find_plugin_registrar(sess.diagnostic(), &hir_map)
-        }));
-    sess.proc_macro_decls_static
-        .set(proc_macro_decls::find(&hir_map));
-
     let mut local_providers = ty::query::Providers::default();
     default_provide(&mut local_providers);
     codegen_backend.provide(&mut local_providers);
@@ -1248,6 +1243,14 @@ where
             // tcx available.
             time(sess, "dep graph tcx init", || rustc_incremental::dep_graph_tcx_init(tcx));
 
+            time(sess, "looking for plugin registrar", || {
+                plugin::build::find_plugin_registrar(tcx)
+            });
+
+            time(sess, "looking for derive registrar", || {
+                proc_macro_decls::find(tcx)
+            });
+
             time(sess, "loop checking", || loops::check_crate(tcx));
 
             time(sess, "attribute checking", || {

src/librustc_driver/driver.rs

@@ -1,15 +1,25 @@
 use rustc::hir::itemlikevisit::ItemLikeVisitor;
-use rustc::hir::map::Map;
+use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
 use rustc::hir;
+use rustc::ty::TyCtxt;
+use rustc::ty::query::Providers;
 use syntax::ast;
 use syntax::attr;
 
-pub fn find(hir_map: &Map) -> Option<ast::NodeId> {
-    let krate = hir_map.krate();
+pub fn find<'tcx>(tcx: TyCtxt<'_, 'tcx, 'tcx>) -> Option<DefId> {
+    tcx.proc_macro_decls_static(LOCAL_CRATE)
+}
+
+fn proc_macro_decls_static<'tcx>(
+    tcx: TyCtxt<'_, 'tcx, 'tcx>,
+    cnum: CrateNum,
+) -> Option<DefId> {
+    assert_eq!(cnum, LOCAL_CRATE);
 
     let mut finder = Finder { decls: None };
-    krate.visit_all_item_likes(&mut finder);
-    finder.decls
+    tcx.hir().krate().visit_all_item_likes(&mut finder);
+
+    finder.decls.map(|id| tcx.hir().local_def_id(id))
 }
 
 struct Finder {
@@ -30,3 +40,9 @@ impl<'v> ItemLikeVisitor<'v> for Finder {
     }
 }
 
+pub(crate) fn provide(providers: &mut Providers<'_>) {
+    *providers = Providers {
+        proc_macro_decls_static,
+        ..*providers
+    };
+}

src/librustc_driver/proc_macro_decls.rs

@@ -19,7 +19,7 @@
 //! a `pub fn new()`.
 
 use rustc::hir::def::Def;
-use rustc::hir::def_id::DefId;
+use rustc::hir::def_id::{DefId, LOCAL_CRATE};
 use rustc::ty::{self, Ty};
 use hir::Node;
 use util::nodemap::NodeSet;
@@ -860,7 +860,7 @@ impl LintPass for PluginAsLibrary {
 
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for PluginAsLibrary {
     fn check_item(&mut self, cx: &LateContext, it: &hir::Item) {
-        if cx.sess().plugin_registrar_fn.get().is_some() {
+        if cx.tcx.plugin_registrar_fn(LOCAL_CRATE).is_some() {
             // We're compiling a plugin; it's fine to link other plugins.
             return;
         }

src/librustc_lint/builtin.rs

@@ -482,13 +482,10 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             has_global_allocator: has_global_allocator,
             has_panic_handler: has_panic_handler,
             has_default_lib_allocator: has_default_lib_allocator,
-            plugin_registrar_fn: tcx.sess
-                .plugin_registrar_fn
-                .get()
-                .map(|id| tcx.hir().local_def_id(id).index),
+            plugin_registrar_fn: tcx.plugin_registrar_fn(LOCAL_CRATE).map(|id| id.index),
             proc_macro_decls_static: if is_proc_macro {
-                let id = tcx.sess.proc_macro_decls_static.get().unwrap();
-                Some(tcx.hir().local_def_id(id).index)
+                let id = tcx.proc_macro_decls_static(LOCAL_CRATE).unwrap();
+                Some(id.index)
             } else {
                 None
             },

src/librustc_metadata/encoder.rs

@@ -2,11 +2,12 @@
 
 use syntax::ast;
 use syntax::attr;
-use errors;
 use syntax_pos::Span;
-use rustc::hir::map::Map;
 use rustc::hir::itemlikevisit::ItemLikeVisitor;
 use rustc::hir;
+use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
+use rustc::ty::TyCtxt;
+use rustc::ty::query::Providers;
 
 struct RegistrarFinder {
     registrars: Vec<(ast::NodeId, Span)> ,
@@ -30,21 +31,27 @@ impl<'v> ItemLikeVisitor<'v> for RegistrarFinder {
 }
 
 /// Find the function marked with `#[plugin_registrar]`, if any.
-pub fn find_plugin_registrar(diagnostic: &errors::Handler,
-                             hir_map: &Map)
-                             -> Option<ast::NodeId> {
-    let krate = hir_map.krate();
+pub fn find_plugin_registrar<'tcx>(tcx: TyCtxt<'_, 'tcx, 'tcx>) -> Option<DefId> {
+    tcx.plugin_registrar_fn(LOCAL_CRATE)
+}
+
+fn plugin_registrar_fn<'tcx>(
+    tcx: TyCtxt<'_, 'tcx, 'tcx>,
+    cnum: CrateNum,
+) -> Option<DefId> {
+    assert_eq!(cnum, LOCAL_CRATE);
 
     let mut finder = RegistrarFinder { registrars: Vec::new() };
-    krate.visit_all_item_likes(&mut finder);
+    tcx.hir().krate().visit_all_item_likes(&mut finder);
 
     match finder.registrars.len() {
         0 => None,
         1 => {
             let (node_id, _) = finder.registrars.pop().unwrap();
-            Some(node_id)
+            Some(tcx.hir().local_def_id(node_id))
         },
         _ => {
+            let diagnostic = tcx.sess.diagnostic();
             let mut e = diagnostic.struct_err("multiple plugin registration functions found");
             for &(_, span) in &finder.registrars {
                 e.span_note(span, "one is here");
@@ -55,3 +62,11 @@ pub fn find_plugin_registrar(diagnostic: &errors::Handler,
         }
     }
 }
+
+
+pub fn provide(providers: &mut Providers<'_>) {
+    *providers = Providers {
+        plugin_registrar_fn,
+        ..*providers
+    };
+}