Rollup merge of #130294 - nnethercote:more-lifetimes, r=lcnr

Lifetime cleanups

The last commit is very opinionated, let's see how we go.

r? `@oli-obk`

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -3553,7 +3553,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         location: Location,
         mpi: MovePathIndex,
     ) -> (Vec<MoveSite>, Vec<Location>) {
-        fn predecessor_locations<'tcx, 'a>(
+        fn predecessor_locations<'a, 'tcx>(
             body: &'a mir::Body<'tcx>,
             location: Location,
         ) -> impl Iterator<Item = Location> + Captures<'tcx> + 'a {

compiler/rustc_borrowck/src/diagnostics/find_use.rs

@@ -21,15 +21,15 @@ pub(crate) fn find<'tcx>(
     uf.find()
 }
 
-struct UseFinder<'cx, 'tcx> {
-    body: &'cx Body<'tcx>,
-    regioncx: &'cx Rc<RegionInferenceContext<'tcx>>,
+struct UseFinder<'a, 'tcx> {
+    body: &'a Body<'tcx>,
+    regioncx: &'a Rc<RegionInferenceContext<'tcx>>,
     tcx: TyCtxt<'tcx>,
     region_vid: RegionVid,
     start_point: Location,
 }
 
-impl<'cx, 'tcx> UseFinder<'cx, 'tcx> {
+impl<'a, 'tcx> UseFinder<'a, 'tcx> {
     fn find(&mut self) -> Option<Cause> {
         let mut queue = VecDeque::new();
         let mut visited = FxIndexSet::default();
@@ -93,8 +93,8 @@ impl<'cx, 'tcx> UseFinder<'cx, 'tcx> {
     }
 }
 
-struct DefUseVisitor<'cx, 'tcx> {
-    body: &'cx Body<'tcx>,
+struct DefUseVisitor<'a, 'tcx> {
+    body: &'a Body<'tcx>,
     tcx: TyCtxt<'tcx>,
     region_vid: RegionVid,
     def_use_result: Option<DefUseResult>,
@@ -106,7 +106,7 @@ enum DefUseResult {
     UseDrop { local: Local },
 }
 
-impl<'cx, 'tcx> Visitor<'tcx> for DefUseVisitor<'cx, 'tcx> {
+impl<'a, 'tcx> Visitor<'tcx> for DefUseVisitor<'a, 'tcx> {
     fn visit_local(&mut self, local: Local, context: PlaceContext, _: Location) {
         let local_ty = self.body.local_decls[local].ty;
 

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -558,7 +558,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                 ty: Ty<'tcx>,
                 suggested: bool,
             }
-            impl<'a, 'cx, 'tcx> Visitor<'tcx> for SuggestIndexOperatorAlternativeVisitor<'a, 'cx, 'tcx> {
+            impl<'a, 'infcx, 'tcx> Visitor<'tcx> for SuggestIndexOperatorAlternativeVisitor<'a, 'infcx, 'tcx> {
                 fn visit_stmt(&mut self, stmt: &'tcx hir::Stmt<'tcx>) {
                     hir::intravisit::walk_stmt(self, stmt);
                     let expr = match stmt.kind {