Merge remote-tracking branch 'upstream/master' into rustup

clippy_lints/src/future_not_send.rs

@@ -92,13 +92,8 @@ impl<'tcx> LateLintPass<'tcx> for FutureNotSend {
                         |db| {
                             cx.tcx.infer_ctxt().enter(|infcx| {
                                 for FulfillmentError { obligation, .. } in send_errors {
-                                    infcx.maybe_note_obligation_cause_for_async_await(
-                                        db,
-                                        &obligation,
-                                    );
-                                    if let Trait(trait_pred, _) =
-                                        obligation.predicate.skip_binders()
-                                    {
+                                    infcx.maybe_note_obligation_cause_for_async_await(db, &obligation);
+                                    if let Trait(trait_pred, _) = obligation.predicate.skip_binders() {
                                         db.note(&format!(
                                             "`{}` doesn't implement `{}`",
                                             trait_pred.self_ty(),

clippy_lints/src/loops.rs

@@ -2950,7 +2950,7 @@ fn check_needless_collect_indirect_usage<'tcx>(expr: &'tcx Expr<'_>, cx: &LateCo
         for ref stmt in block.stmts {
             if_chain! {
                 if let StmtKind::Local(
-                    Local { pat: Pat { kind: PatKind::Binding(_, _, ident, .. ), .. },
+                    Local { pat: Pat { hir_id: pat_id, kind: PatKind::Binding(_, _, ident, .. ), .. },
                     init: Some(ref init_expr), .. }
                 ) = stmt.kind;
                 if let ExprKind::MethodCall(ref method_name, _, &[ref iter_source], ..) = init_expr.kind;
@@ -2964,6 +2964,16 @@ fn check_needless_collect_indirect_usage<'tcx>(expr: &'tcx Expr<'_>, cx: &LateCo
                 if let Some(iter_calls) = detect_iter_and_into_iters(block, *ident);
                 if iter_calls.len() == 1;
                 then {
+                    let mut used_count_visitor = UsedCountVisitor {
+                        cx,
+                        id: *pat_id,
+                        count: 0,
+                    };
+                    walk_block(&mut used_count_visitor, block);
+                    if used_count_visitor.count > 1 {
+                        return;
+                    }
+
                     // Suggest replacing iter_call with iter_replacement, and removing stmt
                     let iter_call = &iter_calls[0];
                     span_lint_and_then(
@@ -3087,6 +3097,28 @@ impl<'tcx> Visitor<'tcx> for IterFunctionVisitor {
     }
 }
 
+struct UsedCountVisitor<'a, 'tcx> {
+    cx: &'a LateContext<'tcx>,
+    id: HirId,
+    count: usize,
+}
+
+impl<'a, 'tcx> Visitor<'tcx> for UsedCountVisitor<'a, 'tcx> {
+    type Map = Map<'tcx>;
+
+    fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
+        if same_var(self.cx, expr, self.id) {
+            self.count += 1;
+        } else {
+            walk_expr(self, expr);
+        }
+    }
+
+    fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
+        NestedVisitorMap::OnlyBodies(self.cx.tcx.hir())
+    }
+}
+
 /// Detect the occurrences of calls to `iter` or `into_iter` for the
 /// given identifier
 fn detect_iter_and_into_iters<'tcx>(block: &'tcx Block<'tcx>, identifier: Ident) -> Option<Vec<IterFunction>> {

clippy_lints/src/types.rs

@@ -8,6 +8,7 @@ use if_chain::if_chain;
 use rustc_ast::{FloatTy, IntTy, LitFloatType, LitIntType, LitKind, UintTy};
 use rustc_errors::{Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
+use rustc_hir::def::Res;
 use rustc_hir::intravisit::{walk_body, walk_expr, walk_ty, FnKind, NestedVisitorMap, Visitor};
 use rustc_hir::{
     BinOpKind, Block, Body, Expr, ExprKind, FnDecl, FnRetTy, FnSig, GenericArg, GenericBounds, GenericParamKind, HirId,
@@ -1632,7 +1633,14 @@ impl<'tcx> LateLintPass<'tcx> for Casts {
         if expr.span.from_expansion() {
             return;
         }
-        if let ExprKind::Cast(ref ex, _) = expr.kind {
+        if let ExprKind::Cast(ref ex, cast_to) = expr.kind {
+            if let TyKind::Path(QPath::Resolved(_, path)) = cast_to.kind {
+                if let Res::Def(_, def_id) = path.res {
+                    if cx.tcx.has_attr(def_id, sym::cfg) || cx.tcx.has_attr(def_id, sym::cfg_attr) {
+                        return;
+                    }
+                }
+            }
             let (cast_from, cast_to) = (cx.typeck_results().expr_ty(ex), cx.typeck_results().expr_ty(expr));
             lint_fn_to_numeric_cast(cx, expr, ex, cast_from, cast_to);
             if let Some(lit) = get_numeric_literal(ex) {