From 07b37cf791c69c5359a058402495fe45d4657f66 Mon Sep 17 00:00:00 2001
From: LeSeulArtichaut <leseulartichaut@gmail.com>
Date: Sat, 14 Nov 2020 22:16:16 +0100
Subject: [PATCH] Use `TypeVisitor::BreakTy` in `ProhibitOpaqueTypes`

---
 compiler/rustc_lint/src/types.rs | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs
index 1607b53d10cbe..aaedd53c0f611 100644
--- a/compiler/rustc_lint/src/types.rs
+++ b/compiler/rustc_lint/src/types.rs
@@ -1131,18 +1131,14 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
     fn check_for_opaque_ty(&mut self, sp: Span, ty: Ty<'tcx>) -> bool {
         struct ProhibitOpaqueTypes<'a, 'tcx> {
             cx: &'a LateContext<'tcx>,
-            ty: Option<Ty<'tcx>>,
         };
 
         impl<'a, 'tcx> ty::fold::TypeVisitor<'tcx> for ProhibitOpaqueTypes<'a, 'tcx> {
-            type BreakTy = ();
+            type BreakTy = Ty<'tcx>;
 
             fn visit_ty(&mut self, ty: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
                 match ty.kind() {
-                    ty::Opaque(..) => {
-                        self.ty = Some(ty);
-                        ControlFlow::BREAK
-                    }
+                    ty::Opaque(..) => ControlFlow::Break(ty),
                     // Consider opaque types within projections FFI-safe if they do not normalize
                     // to more opaque types.
                     ty::Projection(..) => {
@@ -1161,9 +1157,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
             }
         }
 
-        let mut visitor = ProhibitOpaqueTypes { cx: self.cx, ty: None };
-        ty.visit_with(&mut visitor);
-        if let Some(ty) = visitor.ty {
+        if let Some(ty) = ty.visit_with(&mut ProhibitOpaqueTypes { cx: self.cx }).break_value() {
             self.emit_ffi_unsafe_type_lint(ty, sp, "opaque types have no C equivalent", None);
             true
         } else {