rustc_middle: Remove Option from module_reexports query

Author: petrochenkov

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -1327,8 +1327,8 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 }
             }));
 
-            if let Some(reexports) = tcx.module_reexports(local_def_id) {
-                assert!(!reexports.is_empty());
+            let reexports = tcx.module_reexports(local_def_id);
+            if !reexports.is_empty() {
                 record_array!(self.tables.module_reexports[def_id] <- reexports);
             }
         }

compiler/rustc_middle/src/query/mod.rs

@@ -1510,7 +1510,7 @@ rustc_queries! {
         desc { "getting traits in scope at a block" }
     }
 
-    query module_reexports(def_id: LocalDefId) -> Option<&'tcx [ModChild]> {
+    query module_reexports(def_id: LocalDefId) -> &'tcx [ModChild] {
         desc { |tcx| "looking up reexports of module `{}`", tcx.def_path_str(def_id.to_def_id()) }
     }
 

compiler/rustc_middle/src/ty/context.rs

@@ -2502,7 +2502,7 @@ pub struct DeducedParamAttrs {
 
 pub fn provide(providers: &mut ty::query::Providers) {
     providers.module_reexports =
-        |tcx, id| tcx.resolutions(()).reexport_map.get(&id).map(|v| &v[..]);
+        |tcx, id| tcx.resolutions(()).reexport_map.get(&id).map_or(&[], |v| &v[..]);
     providers.maybe_unused_trait_imports =
         |tcx, ()| &tcx.resolutions(()).maybe_unused_trait_imports;
     providers.names_imported_by_glob_use = |tcx, id| {

compiler/rustc_privacy/src/lib.rs

@@ -515,16 +515,12 @@ impl<'tcx> EmbargoVisitor<'tcx> {
             let vis = self.tcx.local_visibility(item_id.owner_id.def_id);
             self.update_macro_reachable_def(item_id.owner_id.def_id, def_kind, vis, defining_mod);
         }
-        if let Some(exports) = self.tcx.module_reexports(module_def_id) {
-            for export in exports {
-                if export.vis.is_accessible_from(defining_mod, self.tcx) {
-                    if let Res::Def(def_kind, def_id) = export.res {
-                        if let Some(def_id) = def_id.as_local() {
-                            let vis = self.tcx.local_visibility(def_id);
-                            self.update_macro_reachable_def(def_id, def_kind, vis, defining_mod);
-                        }
-                    }
-                }
+        for export in self.tcx.module_reexports(module_def_id) {
+            if export.vis.is_accessible_from(defining_mod, self.tcx)
+                && let Res::Def(def_kind, def_id) = export.res
+                && let Some(def_id) = def_id.as_local() {
+                let vis = self.tcx.local_visibility(def_id);
+                self.update_macro_reachable_def(def_id, def_kind, vis, defining_mod);
             }
         }
     }

src/librustdoc/clean/inline.rs

@@ -153,7 +153,6 @@ pub(crate) fn try_inline_glob(
             let reexports = cx
                 .tcx
                 .module_reexports(current_mod)
-                .unwrap_or_default()
                 .iter()
                 .filter_map(|child| child.res.opt_def_id())
                 .collect();

src/librustdoc/clean/mod.rs

@@ -2062,7 +2062,7 @@ pub(crate) fn reexport_chain<'tcx>(
     import_def_id: LocalDefId,
     target_def_id: LocalDefId,
 ) -> &'tcx [Reexport] {
-    for child in tcx.module_reexports(tcx.local_parent(import_def_id)).unwrap_or_default() {
+    for child in tcx.module_reexports(tcx.local_parent(import_def_id)) {
         if child.res.opt_def_id() == Some(target_def_id.to_def_id())
             && child.reexport_chain[0].id() == Some(import_def_id.to_def_id())
         {

src/librustdoc/visit_ast.rs

@@ -133,7 +133,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
         // is declared but also a reexport of itself producing two exports of the same
         // macro in the same module.
         let mut inserted = FxHashSet::default();
-        for export in self.cx.tcx.module_reexports(CRATE_DEF_ID).unwrap_or(&[]) {
+        for export in self.cx.tcx.module_reexports(CRATE_DEF_ID) {
             if let Res::Def(DefKind::Macro(_), def_id) = export.res &&
                 let Some(local_def_id) = def_id.as_local() &&
                 self.cx.tcx.has_attr(def_id, sym::macro_export) &&