Rollup of 9 pull requests

compiler/rustc_ast/src/mut_visit.rs

@@ -1380,7 +1380,17 @@ pub fn noop_flat_map_stmt<T: MutVisitor>(
 ) -> SmallVec<[Stmt; 1]> {
     vis.visit_id(&mut id);
     vis.visit_span(&mut span);
-    noop_flat_map_stmt_kind(kind, vis).into_iter().map(|kind| Stmt { id, kind, span }).collect()
+    let stmts: SmallVec<_> = noop_flat_map_stmt_kind(kind, vis)
+        .into_iter()
+        .map(|kind| Stmt { id, kind, span })
+        .collect();
+    if stmts.len() > 1 {
+        panic!(
+            "cloning statement `NodeId`s is prohibited by default, \
+             the visitor should implement custom statement visiting"
+        );
+    }
+    stmts
 }
 
 pub fn noop_flat_map_stmt_kind<T: MutVisitor>(

compiler/rustc_codegen_cranelift/src/debuginfo/mod.rs

@@ -66,7 +66,7 @@ impl<'tcx> DebugContext<'tcx> {
             rustc_interface::util::version_str().unwrap_or("unknown version"),
             cranelift_codegen::VERSION,
         );
-        let comp_dir = tcx.sess.opts.working_dir.to_string_lossy(false).into_owned();
+        let comp_dir = tcx.sess.opts.working_dir.to_string_lossy(FileNameDisplayPreference::Remapped).into_owned();
         let (name, file_info) = match tcx.sess.local_crate_source_file.clone() {
             Some(path) => {
                 let name = path.to_string_lossy().into_owned();

compiler/rustc_codegen_cranelift/src/lib.rs

@@ -74,7 +74,7 @@ mod vtable;
 mod prelude {
     pub(crate) use std::convert::{TryFrom, TryInto};
 
-    pub(crate) use rustc_span::Span;
+    pub(crate) use rustc_span::{Span, FileNameDisplayPreference};
 
     pub(crate) use rustc_hir::def_id::{DefId, LOCAL_CRATE};
     pub(crate) use rustc_middle::bug;

compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs

@@ -35,6 +35,7 @@ use rustc_middle::ty::{self, AdtKind, GeneratorSubsts, ParamEnv, Ty, TyCtxt};
 use rustc_middle::{bug, span_bug};
 use rustc_session::config::{self, DebugInfo};
 use rustc_span::symbol::{Interner, Symbol};
+use rustc_span::FileNameDisplayPreference;
 use rustc_span::{self, SourceFile, SourceFileHash, Span};
 use rustc_target::abi::{Abi, Align, HasDataLayout, Integer, LayoutOf, TagEncoding};
 use rustc_target::abi::{Int, Pointer, F32, F64};
@@ -771,7 +772,13 @@ pub fn file_metadata(cx: &CodegenCx<'ll, '_>, source_file: &SourceFile) -> &'ll
     let hash = Some(&source_file.src_hash);
     let file_name = Some(source_file.name.prefer_remapped().to_string());
     let directory = if source_file.is_real_file() && !source_file.is_imported() {
-        Some(cx.sess().opts.working_dir.to_string_lossy(false).to_string())
+        Some(
+            cx.sess()
+                .opts
+                .working_dir
+                .to_string_lossy(FileNameDisplayPreference::Remapped)
+                .to_string(),
+        )
     } else {
         // If the path comes from an upstream crate we assume it has been made
         // independent of the compiler's working directory one way or another.
@@ -999,7 +1006,7 @@ pub fn compile_unit_metadata(
     let producer = format!("clang LLVM ({})", rustc_producer);
 
     let name_in_debuginfo = name_in_debuginfo.to_string_lossy();
-    let work_dir = tcx.sess.opts.working_dir.to_string_lossy(false);
+    let work_dir = tcx.sess.opts.working_dir.to_string_lossy(FileNameDisplayPreference::Remapped);
     let flags = "\0";
     let output_filenames = tcx.output_filenames(());
     let out_dir = &output_filenames.out_directory;

compiler/rustc_errors/src/annotate_snippet_emitter_writer.rs

@@ -126,7 +126,7 @@ impl AnnotateSnippetEmitterWriter {
             }
             // owned: line source, line index, annotations
             type Owned = (String, usize, Vec<crate::snippet::Annotation>);
-            let filename = primary_lo.file.name.prefer_local();
+            let filename = source_map.filename_for_diagnostics(&primary_lo.file.name);
             let origin = filename.to_string_lossy();
             let annotated_files: Vec<Owned> = annotated_files
                 .into_iter()

compiler/rustc_errors/src/emitter.rs

@@ -1320,7 +1320,7 @@ impl EmitterWriter {
                         buffer_msg_line_offset,
                         &format!(
                             "{}:{}:{}",
-                            loc.file.name.prefer_local(),
+                            sm.filename_for_diagnostics(&loc.file.name),
                             sm.doctest_offset_line(&loc.file.name, loc.line),
                             loc.col.0 + 1,
                         ),
@@ -1334,7 +1334,7 @@ impl EmitterWriter {
                         0,
                         &format!(
                             "{}:{}:{}: ",
-                            loc.file.name.prefer_local(),
+                            sm.filename_for_diagnostics(&loc.file.name),
                             sm.doctest_offset_line(&loc.file.name, loc.line),
                             loc.col.0 + 1,
                         ),
@@ -1362,12 +1362,12 @@ impl EmitterWriter {
                     };
                     format!(
                         "{}:{}{}",
-                        annotated_file.file.name.prefer_local(),
+                        sm.filename_for_diagnostics(&annotated_file.file.name),
                         sm.doctest_offset_line(&annotated_file.file.name, first_line.line_index),
                         col
                     )
                 } else {
-                    format!("{}", annotated_file.file.name.prefer_local())
+                    format!("{}", sm.filename_for_diagnostics(&annotated_file.file.name))
                 };
                 buffer.append(buffer_msg_line_offset + 1, &loc, Style::LineAndColumn);
                 for _ in 0..max_line_num_len {

compiler/rustc_errors/src/json.rs

@@ -464,7 +464,7 @@ impl DiagnosticSpan {
         });
 
         DiagnosticSpan {
-            file_name: start.file.name.prefer_local().to_string(),
+            file_name: je.sm.filename_for_diagnostics(&start.file.name).to_string(),
             byte_start: start.file.original_relative_byte_pos(span.lo()).0,
             byte_end: start.file.original_relative_byte_pos(span.hi()).0,
             line_start: start.line,

compiler/rustc_expand/src/base.rs

@@ -1113,7 +1113,7 @@ impl<'a> ExtCtxt<'a> {
                         span,
                         &format!(
                             "cannot resolve relative path in non-file source `{}`",
-                            other.prefer_local()
+                            self.source_map().filename_for_diagnostics(&other)
                         ),
                     ));
                 }

compiler/rustc_expand/src/expand.rs

@@ -12,7 +12,7 @@ use rustc_ast::ptr::P;
 use rustc_ast::token;
 use rustc_ast::tokenstream::TokenStream;
 use rustc_ast::visit::{self, AssocCtxt, Visitor};
-use rustc_ast::{AstLike, Block, Inline, ItemKind, Local, MacArgs, MacCall};
+use rustc_ast::{AstLike, Block, Inline, ItemKind, MacArgs, MacCall};
 use rustc_ast::{MacCallStmt, MacStmtStyle, MetaItemKind, ModKind, NestedMetaItem};
 use rustc_ast::{NodeId, PatKind, Path, StmtKind, Unsafe};
 use rustc_ast_pretty::pprust;
@@ -559,7 +559,7 @@ impl<'a, 'b> MacroExpander<'a, 'b> {
         self.cx.force_mode = orig_force_mode;
 
         // Finally incorporate all the expanded macros into the input AST fragment.
-        let mut placeholder_expander = PlaceholderExpander::new(self.cx, self.monotonic);
+        let mut placeholder_expander = PlaceholderExpander::default();
         while let Some(expanded_fragments) = expanded_fragments.pop() {
             for (expn_id, expanded_fragment) in expanded_fragments.into_iter().rev() {
                 placeholder_expander
@@ -1061,13 +1061,51 @@ impl<'a, 'b> InvocationCollector<'a, 'b> {
         attr
     }
 
+    fn take_stmt_bang(
+        &mut self,
+        stmt: ast::Stmt,
+    ) -> Result<(bool, MacCall, Vec<ast::Attribute>), ast::Stmt> {
+        match stmt.kind {
+            StmtKind::MacCall(mac) => {
+                let MacCallStmt { mac, style, attrs, .. } = mac.into_inner();
+                Ok((style == MacStmtStyle::Semicolon, mac, attrs.into()))
+            }
+            StmtKind::Item(ref item) if matches!(item.kind, ItemKind::MacCall(..)) => {
+                match stmt.kind {
+                    StmtKind::Item(item) => match item.into_inner() {
+                        ast::Item { kind: ItemKind::MacCall(mac), attrs, .. } => {
+                            Ok((mac.args.need_semicolon(), mac, attrs))
+                        }
+                        _ => unreachable!(),
+                    },
+                    _ => unreachable!(),
+                }
+            }
+            StmtKind::Semi(ref expr) if matches!(expr.kind, ast::ExprKind::MacCall(..)) => {
+                match stmt.kind {
+                    StmtKind::Semi(expr) => match expr.into_inner() {
+                        ast::Expr { kind: ast::ExprKind::MacCall(mac), attrs, .. } => {
+                            Ok((mac.args.need_semicolon(), mac, attrs.into()))
+                        }
+                        _ => unreachable!(),
+                    },
+                    _ => unreachable!(),
+                }
+            }
+            StmtKind::Local(..) | StmtKind::Empty | StmtKind::Item(..) | StmtKind::Semi(..) => {
+                Err(stmt)
+            }
+            StmtKind::Expr(..) => unreachable!(),
+        }
+    }
+
     fn configure<T: AstLike>(&mut self, node: T) -> Option<T> {
         self.cfg.configure(node)
     }
 
     // Detect use of feature-gated or invalid attributes on macro invocations
     // since they will not be detected after macro expansion.
-    fn check_attributes(&mut self, attrs: &[ast::Attribute], call: &MacCall) {
+    fn check_attributes(&self, attrs: &[ast::Attribute], call: &MacCall) {
         let features = self.cx.ecfg.features.unwrap();
         let mut attrs = attrs.iter().peekable();
         let mut span: Option<Span> = None;
@@ -1177,11 +1215,6 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
         });
     }
 
-    // This is needed in order to set `lint_node_id` for `let` statements
-    fn visit_local(&mut self, local: &mut P<Local>) {
-        assign_id!(self, &mut local.id, || noop_visit_local(local, self));
-    }
-
     fn flat_map_arm(&mut self, arm: ast::Arm) -> SmallVec<[ast::Arm; 1]> {
         let mut arm = configure!(self, arm);
 
@@ -1299,31 +1332,39 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
     fn flat_map_stmt(&mut self, stmt: ast::Stmt) -> SmallVec<[ast::Stmt; 1]> {
         let mut stmt = configure!(self, stmt);
 
-        // we'll expand attributes on expressions separately
-        if !stmt.is_expr() {
+        // We pull macro invocations (both attributes and fn-like macro calls) out of their
+        // `StmtKind`s and treat them as statement macro invocations, not as items or expressions.
+        // FIXME: invocations in semicolon-less expressions positions are expanded as expressions,
+        // changing that requires some compatibility measures.
+        let mut stmt = if !stmt.is_expr() {
             if let Some(attr) = self.take_first_attr(&mut stmt) {
                 return self
                     .collect_attr(attr, Annotatable::Stmt(P(stmt)), AstFragmentKind::Stmts)
                     .make_stmts();
             }
-        }
 
-        if let StmtKind::MacCall(mac) = stmt.kind {
-            let MacCallStmt { mac, style, attrs, tokens: _ } = mac.into_inner();
-            self.check_attributes(&attrs, &mac);
-            let mut placeholder =
-                self.collect_bang(mac, stmt.span, AstFragmentKind::Stmts).make_stmts();
-
-            // If this is a macro invocation with a semicolon, then apply that
-            // semicolon to the final statement produced by expansion.
-            if style == MacStmtStyle::Semicolon {
-                if let Some(stmt) = placeholder.pop() {
-                    placeholder.push(stmt.add_trailing_semicolon());
+            let span = stmt.span;
+            match self.take_stmt_bang(stmt) {
+                Ok((add_semicolon, mac, attrs)) => {
+                    self.check_attributes(&attrs, &mac);
+                    let mut stmts =
+                        self.collect_bang(mac, span, AstFragmentKind::Stmts).make_stmts();
+
+                    // If this is a macro invocation with a semicolon, then apply that
+                    // semicolon to the final statement produced by expansion.
+                    if add_semicolon {
+                        if let Some(stmt) = stmts.pop() {
+                            stmts.push(stmt.add_trailing_semicolon());
+                        }
+                    }
+
+                    return stmts;
                 }
+                Err(stmt) => stmt,
             }
-
-            return placeholder;
-        }
+        } else {
+            stmt
+        };
 
         // The only way that we can end up with a `MacCall` expression statement,
         // (as opposed to a `StmtKind::MacCall`) is if we have a macro as the
@@ -1338,14 +1379,7 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> {
             }
         }
 
-        // The placeholder expander gives ids to statements, so we avoid folding the id here.
-        // We don't use `assign_id!` - it will be called when we visit statement's contents
-        // (e.g. an expression, item, or local)
-        let ast::Stmt { id, kind, span } = stmt;
-        let res = noop_flat_map_stmt_kind(kind, self)
-            .into_iter()
-            .map(|kind| ast::Stmt { id, kind, span })
-            .collect();
+        let res = assign_id!(self, &mut stmt.id, || noop_flat_map_stmt(stmt, self));
 
         self.cx.current_expansion.is_trailing_mac = false;
         res

compiler/rustc_expand/src/placeholders.rs

@@ -1,4 +1,3 @@
-use crate::base::ExtCtxt;
 use crate::expand::{AstFragment, AstFragmentKind};
 
 use rustc_ast as ast;
@@ -175,17 +174,12 @@ pub fn placeholder(
     }
 }
 
-pub struct PlaceholderExpander<'a, 'b> {
+#[derive(Default)]
+pub struct PlaceholderExpander {
     expanded_fragments: FxHashMap<ast::NodeId, AstFragment>,
-    cx: &'a mut ExtCtxt<'b>,
-    monotonic: bool,
 }
 
-impl<'a, 'b> PlaceholderExpander<'a, 'b> {
-    pub fn new(cx: &'a mut ExtCtxt<'b>, monotonic: bool) -> Self {
-        PlaceholderExpander { cx, expanded_fragments: FxHashMap::default(), monotonic }
-    }
-
+impl PlaceholderExpander {
     pub fn add(&mut self, id: ast::NodeId, mut fragment: AstFragment) {
         fragment.mut_visit_with(self);
         self.expanded_fragments.insert(id, fragment);
@@ -196,7 +190,7 @@ impl<'a, 'b> PlaceholderExpander<'a, 'b> {
     }
 }
 
-impl<'a, 'b> MutVisitor for PlaceholderExpander<'a, 'b> {
+impl MutVisitor for PlaceholderExpander {
     fn flat_map_arm(&mut self, arm: ast::Arm) -> SmallVec<[ast::Arm; 1]> {
         if arm.is_placeholder {
             self.remove(arm.id).make_arms()
@@ -360,15 +354,4 @@ impl<'a, 'b> MutVisitor for PlaceholderExpander<'a, 'b> {
             _ => noop_visit_ty(ty, self),
         }
     }
-
-    fn visit_block(&mut self, block: &mut P<ast::Block>) {
-        noop_visit_block(block, self);
-
-        for stmt in block.stmts.iter_mut() {
-            if self.monotonic {
-                assert_eq!(stmt.id, ast::DUMMY_NODE_ID);
-                stmt.id = self.cx.resolver.next_node_id();
-            }
-        }
-    }
 }

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -1630,14 +1630,11 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                 (TypeError::Sorts(values), extra) => {
                     let sort_string = |ty: Ty<'tcx>| match (extra, ty.kind()) {
                         (true, ty::Opaque(def_id, _)) => {
-                            let pos = self
-                                .tcx
-                                .sess
-                                .source_map()
-                                .lookup_char_pos(self.tcx.def_span(*def_id).lo());
+                            let sm = self.tcx.sess.source_map();
+                            let pos = sm.lookup_char_pos(self.tcx.def_span(*def_id).lo());
                             format!(
                                 " (opaque type at <{}:{}:{}>)",
-                                pos.file.name.prefer_local(),
+                                sm.filename_for_diagnostics(&pos.file.name),
                                 pos.line,
                                 pos.col.to_usize() + 1,
                             )

compiler/rustc_lint/src/unused.rs

@@ -461,13 +461,16 @@ trait UnusedDelimLint {
         let lhs_needs_parens = {
             let mut innermost = inner;
             loop {
-                if let ExprKind::Binary(_, lhs, _rhs) = &innermost.kind {
-                    innermost = lhs;
-                    if !classify::expr_requires_semi_to_be_stmt(innermost) {
-                        break true;
-                    }
-                } else {
-                    break false;
+                innermost = match &innermost.kind {
+                    ExprKind::Binary(_, lhs, _rhs) => lhs,
+                    ExprKind::Call(fn_, _params) => fn_,
+                    ExprKind::Cast(expr, _ty) => expr,
+                    ExprKind::Type(expr, _ty) => expr,
+                    ExprKind::Index(base, _subscript) => base,
+                    _ => break false,
+                };
+                if !classify::expr_requires_semi_to_be_stmt(innermost) {
+                    break true;
                 }
             }
         };

compiler/rustc_middle/src/mir/mod.rs

@@ -411,8 +411,7 @@ impl<'tcx> Body<'tcx> {
     /// Returns an iterator over all function arguments.
     #[inline]
     pub fn args_iter(&self) -> impl Iterator<Item = Local> + ExactSizeIterator {
-        let arg_count = self.arg_count;
-        (1..arg_count + 1).map(Local::new)
+        (1..self.arg_count + 1).map(Local::new)
     }
 
     /// Returns an iterator over all user-defined variables and compiler-generated temporaries (all
@@ -421,9 +420,7 @@ impl<'tcx> Body<'tcx> {
     pub fn vars_and_temps_iter(
         &self,
     ) -> impl DoubleEndedIterator<Item = Local> + ExactSizeIterator {
-        let arg_count = self.arg_count;
-        let local_count = self.local_decls.len();
-        (arg_count + 1..local_count).map(Local::new)
+        (self.arg_count + 1..self.local_decls.len()).map(Local::new)
     }
 
     #[inline]