use visibility to check unused imports and delete some stmts

Author: bvanjoi

compiler/rustc_ast/src/lib.rs

@@ -53,7 +53,6 @@ pub mod visit;
 
 pub use self::ast::*;
 pub use self::ast_traits::{AstDeref, AstNodeWrapper, HasAttrs, HasNodeId, HasSpan, HasTokens};
-pub use self::format::*;
 
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 

compiler/rustc_codegen_llvm/src/debuginfo/mod.rs

@@ -50,7 +50,6 @@ mod utils;
 
 pub use self::create_scope_map::compute_mir_scopes;
 pub use self::metadata::build_global_var_di_node;
-pub use self::metadata::extend_scope_to_file;
 
 #[allow(non_upper_case_globals)]
 const DW_TAG_auto_variable: c_uint = 0x100;

compiler/rustc_codegen_llvm/src/mono_item.rs

@@ -6,7 +6,6 @@ use crate::llvm;
 use crate::type_of::LayoutLlvmExt;
 use rustc_codegen_ssa::traits::*;
 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
-pub use rustc_middle::mir::mono::MonoItem;
 use rustc_middle::mir::mono::{Linkage, Visibility};
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf};
 use rustc_middle::ty::{self, Instance, TypeVisitableExt};

compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs

@@ -4,9 +4,7 @@ mod arg_matrix;
 mod checks;
 mod suggestions;
 
-pub use _impl::*;
 use rustc_errors::ErrorGuaranteed;
-pub use suggestions::*;
 
 use crate::coercion::DynamicCoerceMany;
 use crate::{Diverges, EnclosingBreakables, Inherited};

compiler/rustc_infer/src/traits/mod.rs

@@ -19,7 +19,6 @@ use rustc_span::Span;
 
 pub use self::FulfillmentErrorCode::*;
 pub use self::ImplSource::*;
-pub use self::ObligationCauseCode::*;
 pub use self::SelectionError::*;
 
 pub use self::engine::{TraitEngine, TraitEngineExt};

compiler/rustc_middle/src/mir/terminator.rs

@@ -3,12 +3,10 @@ use rustc_hir::LangItem;
 use smallvec::SmallVec;
 
 use super::{BasicBlock, InlineAsmOperand, Operand, SourceInfo, TerminatorKind, UnwindAction};
-pub use rustc_ast::Mutability;
 use rustc_macros::HashStable;
 use std::iter;
 use std::slice;
 
-pub use super::query::*;
 use super::*;
 
 impl SwitchTargets {

compiler/rustc_middle/src/ty/assoc.rs

@@ -1,5 +1,3 @@
-pub use self::AssocItemContainer::*;
-
 use crate::ty;
 use rustc_data_structures::sorted_map::SortedIndexMultiMap;
 use rustc_hir as hir;

compiler/rustc_mir_dataflow/src/framework/mod.rs

@@ -48,7 +48,7 @@ mod visitor;
 pub use self::cursor::{AnalysisResults, ResultsClonedCursor, ResultsCursor, ResultsRefCursor};
 pub use self::direction::{Backward, Direction, Forward};
 pub use self::engine::{Engine, EntrySets, Results, ResultsCloned};
-pub use self::lattice::{JoinSemiLattice, MaybeReachable, MeetSemiLattice};
+pub use self::lattice::{JoinSemiLattice, MaybeReachable};
 pub use self::visitor::{visit_results, ResultsVisitable, ResultsVisitor};
 
 /// Analysis domains are all bitsets of various kinds. This trait holds

compiler/rustc_resolve/src/check_unused.rs

@@ -59,7 +59,6 @@ struct UnusedImportCheckVisitor<'a, 'b, 'tcx> {
     base_use_tree: Option<&'a ast::UseTree>,
     base_id: ast::NodeId,
     item_span: Span,
-    base_use_is_pub: bool,
 }
 
 struct ExternCrateToLint {
@@ -146,7 +145,6 @@ impl<'a, 'b, 'tcx> Visitor<'a> for UnusedImportCheckVisitor<'a, 'b, 'tcx> {
             // because this means that they were generated in some fashion by the
             // compiler and we don't need to consider them.
             ast::ItemKind::Use(..) if item.span.is_dummy() => return,
-            ast::ItemKind::Use(..) => self.base_use_is_pub = item.vis.kind.is_pub(),
             ast::ItemKind::ExternCrate(orig_name) => {
                 self.extern_crate_items.push(ExternCrateToLint {
                     id: item.id,
@@ -173,7 +171,7 @@ impl<'a, 'b, 'tcx> Visitor<'a> for UnusedImportCheckVisitor<'a, 'b, 'tcx> {
             self.base_use_tree = Some(use_tree);
         }
 
-        if self.base_use_is_pub {
+        if self.r.effective_visibilities.is_exported(self.r.local_def_id(id)) {
             self.check_import_as_underscore(use_tree, id);
             return;
         }
@@ -332,7 +330,6 @@ impl Resolver<'_, '_> {
             base_use_tree: None,
             base_id: ast::DUMMY_NODE_ID,
             item_span: DUMMY_SP,
-            base_use_is_pub: false,
         };
         visit::walk_crate(&mut visitor, krate);
 

compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs

@@ -20,7 +20,6 @@ use std::ops::ControlFlow;
 
 pub use self::infer_ctxt_ext::*;
 pub use self::type_err_ctxt_ext::*;
-pub use rustc_infer::traits::error_reporting::*;
 
 // When outputting impl candidates, prefer showing those that are more similar.
 //