From ec104e5912417c0fdc8c7cb004c684aea26eb1dc Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Fri, 11 Aug 2017 18:24:27 -0700
Subject: [PATCH] [unsafe-to-break] Mark unsafe is cluster merging is disabled

We were relying on cluster merges not requiring unsafe flagging because
they get merged.  If cluster level requests no merging, then we flag
unsafe when merge would have happened.
---
 src/hb-buffer.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/hb-buffer.cc b/src/hb-buffer.cc
index 89576f012..dc932692b 100644
--- a/src/hb-buffer.cc
+++ b/src/hb-buffer.cc
@@ -550,7 +550,10 @@ hb_buffer_t::merge_clusters_impl (unsigned int start,
 				  unsigned int end)
 {
   if (cluster_level == HB_BUFFER_CLUSTER_LEVEL_CHARACTERS)
+  {
+    unsafe_to_break (start, end);
     return;
+  }
 
   unsigned int cluster = info[start].cluster;