From 6548aefdeb425170cb40f7160cceedf14c97a433 Mon Sep 17 00:00:00 2001
From: Ariel Ben-Yehuda <ariel.byd@gmail.com>
Date: Thu, 18 May 2017 23:58:39 +0300
Subject: [PATCH] fix loops in unwind code in MSVC

I'm not sure how well this works, but it's worth a try.
---
 src/librustc_trans/mir/analyze.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/librustc_trans/mir/analyze.rs b/src/librustc_trans/mir/analyze.rs
index 96ef26d3f6f8..0f95668302c8 100644
--- a/src/librustc_trans/mir/analyze.rs
+++ b/src/librustc_trans/mir/analyze.rs
@@ -260,7 +260,9 @@ pub fn cleanup_kinds<'a, 'tcx>(mir: &mir::Mir<'tcx>) -> IndexVec<mir::BasicBlock
                         result[succ] = CleanupKind::Internal { funclet: funclet };
                     }
                     CleanupKind::Funclet => {
-                        set_successor(funclet, succ);
+                        if funclet != succ {
+                            set_successor(funclet, succ);
+                        }
                     }
                     CleanupKind::Internal { funclet: succ_funclet } => {
                         if funclet != succ_funclet {