From 7ad9ef3c450e538be87a8be90bfcc5b6c9928791 Mon Sep 17 00:00:00 2001
From: est31 <MTest31@outlook.com>
Date: Thu, 17 May 2018 23:50:27 +0200
Subject: [PATCH] CheckLoopVisitor: also visit closure arguments

This turns an ICE on this code:

fn main() {
    |_: [u8; break]| ();
}

from
    'assertion failed: self.tcx.sess.err_count() > 0', librustc_typeck/check/mod.rs
to
    librustc_mir/hair/cx/expr.rs:543: invalid loop id for break: not inside loop scope

which is at a later stage during compilation and most importantly
fixes of bug #50576 will fix this as well.
---
 src/librustc_passes/loops.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/librustc_passes/loops.rs b/src/librustc_passes/loops.rs
index 2368b1aca6948..670097e3a4856 100644
--- a/src/librustc_passes/loops.rs
+++ b/src/librustc_passes/loops.rs
@@ -82,7 +82,8 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
             hir::ExprLoop(ref b, _, source) => {
                 self.with_context(Loop(LoopKind::Loop(source)), |v| v.visit_block(&b));
             }
-            hir::ExprClosure(.., b, _, _) => {
+            hir::ExprClosure(_, ref function_decl, b, _, _) => {
+                self.visit_fn_decl(&function_decl);
                 self.with_context(Closure, |v| v.visit_nested_body(b));
             }
             hir::ExprBlock(ref b, Some(_label)) => {