Remove sess from CheckLoopVisitor.

Author: nnethercote

compiler/rustc_passes/src/loops.rs

@@ -9,7 +9,6 @@ use rustc_middle::hir::nested_filter;
 use rustc_middle::query::Providers;
 use rustc_middle::span_bug;
 use rustc_middle::ty::TyCtxt;
-use rustc_session::Session;
 use rustc_span::hygiene::DesugaringKind;
 use rustc_span::{BytePos, Span};
 use Context::*;
@@ -65,7 +64,6 @@ impl fmt::Display for BreakContextKind {
 
 #[derive(Clone)]
 struct CheckLoopVisitor<'tcx> {
-    sess: &'tcx Session,
     tcx: TyCtxt<'tcx>,
     // Keep track of a stack of contexts, so that suggestions
     // are not made for contexts where it would be incorrect,
@@ -76,12 +74,8 @@ struct CheckLoopVisitor<'tcx> {
 }
 
 fn check_mod_loops(tcx: TyCtxt<'_>, module_def_id: LocalModDefId) {
-    let mut check = CheckLoopVisitor {
-        sess: tcx.sess,
-        tcx,
-        cx_stack: vec![Normal],
-        block_breaks: Default::default(),
-    };
+    let mut check =
+        CheckLoopVisitor { tcx, cx_stack: vec![Normal], block_breaks: Default::default() };
     tcx.hir().visit_item_likes_in_module(module_def_id, &mut check);
     check.report_outside_loop_error();
 }
@@ -213,7 +207,7 @@ impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
                     Ok(loop_id) => Some(loop_id),
                     Err(hir::LoopIdError::OutsideLoopScope) => None,
                     Err(hir::LoopIdError::UnlabeledCfInWhileCondition) => {
-                        self.sess.dcx().emit_err(UnlabeledCfInWhileCondition {
+                        self.tcx.dcx().emit_err(UnlabeledCfInWhileCondition {
                             span: e.span,
                             cf_type: "break",
                         });
@@ -248,7 +242,7 @@ impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
                                     .label
                                     .map_or_else(String::new, |l| format!(" {}", l.ident))
                             );
-                            self.sess.dcx().emit_err(BreakNonLoop {
+                            self.tcx.dcx().emit_err(BreakNonLoop {
                                 span: e.span,
                                 head,
                                 kind: kind.name(),
@@ -280,14 +274,14 @@ impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
                 match destination.target_id {
                     Ok(loop_id) => {
                         if let Node::Block(block) = self.tcx.hir_node(loop_id) {
-                            self.sess.dcx().emit_err(ContinueLabeledBlock {
+                            self.tcx.dcx().emit_err(ContinueLabeledBlock {
                                 span: e.span,
                                 block_span: block.span,
                             });
                         }
                     }
                     Err(hir::LoopIdError::UnlabeledCfInWhileCondition) => {
-                        self.sess.dcx().emit_err(UnlabeledCfInWhileCondition {
+                        self.tcx.dcx().emit_err(UnlabeledCfInWhileCondition {
                             span: e.span,
                             cf_type: "continue",
                         });
@@ -326,7 +320,7 @@ impl<'hir> CheckLoopVisitor<'hir> {
         match self.cx_stack[cx_pos] {
             LabeledBlock | Loop(_) => {}
             Closure(closure_span) => {
-                self.sess.dcx().emit_err(BreakInsideClosure {
+                self.tcx.dcx().emit_err(BreakInsideClosure {
                     span,
                     closure_span,
                     name: &br_cx_kind.to_string(),
@@ -343,7 +337,7 @@ impl<'hir> CheckLoopVisitor<'hir> {
                     hir::CoroutineSource::Closure => "closure",
                     hir::CoroutineSource::Fn => "function",
                 };
-                self.sess.dcx().emit_err(BreakInsideCoroutine {
+                self.tcx.dcx().emit_err(BreakInsideCoroutine {
                     span,
                     coroutine_span,
                     name: &br_cx_kind.to_string(),
@@ -366,7 +360,7 @@ impl<'hir> CheckLoopVisitor<'hir> {
                 self.require_break_cx(br_cx_kind, span, break_span, cx_pos - 1);
             }
             Normal | AnonConst | Fn | UnlabeledBlock(_) | UnlabeledIfBlock(_) | ConstBlock => {
-                self.sess.dcx().emit_err(OutsideLoop {
+                self.tcx.dcx().emit_err(OutsideLoop {
                     spans: vec![span],
                     name: &br_cx_kind.to_string(),
                     is_break: br_cx_kind == BreakContextKind::Break,
@@ -386,15 +380,15 @@ impl<'hir> CheckLoopVisitor<'hir> {
             && self.cx_stack.last() == Some(&LabeledBlock)
             && label.label.is_none()
         {
-            self.sess.dcx().emit_err(UnlabeledInLabeledBlock { span, cf_type });
+            self.tcx.dcx().emit_err(UnlabeledInLabeledBlock { span, cf_type });
             return true;
         }
         false
     }
 
     fn report_outside_loop_error(&self) {
         for (s, block) in &self.block_breaks {
-            self.sess.dcx().emit_err(OutsideLoop {
+            self.tcx.dcx().emit_err(OutsideLoop {
                 spans: block.spans.clone(),
                 name: &block.name,
                 is_break: true,