From 707659490d35e8d66e8bbdcfd93b12dc1387d86c Mon Sep 17 00:00:00 2001
From: Bram Moolenaar <Bram@vim.org>
Date: Sun, 28 Feb 2016 19:28:59 +0100
Subject: [PATCH] patch 7.4.1451 Problem:    Vim hangs when a channel has a
 callback but isn't referenced. Solution:   Have channel_unref() only return
 TRUE when the channel was             actually freed.

---
 src/channel.c         | 7 ++++++-
 src/eval.c            | 5 +----
 src/proto/channel.pro | 2 +-
 src/version.c         | 2 ++
 4 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/channel.c b/src/channel.c
index c6f94ee2b9..5e8c6bd814 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -334,12 +334,17 @@ channel_still_useful(channel_T *channel)
  * Close a channel and free all its resources if there is no further action
  * possible, there is no callback to be invoked or the associated job was
  * killed.
+ * Return TRUE if the channel was freed.
  */
-    void
+    int
 channel_may_free(channel_T *channel)
 {
     if (!channel_still_useful(channel))
+    {
 	channel_free(channel);
+	return TRUE;
+    }
+    return FALSE;
 }
 
 /*
diff --git a/src/eval.c b/src/eval.c
index 4dd400ad98..a208b2a727 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -7747,10 +7747,7 @@ failret:
 channel_unref(channel_T *channel)
 {
     if (channel != NULL && --channel->ch_refcount <= 0)
-    {
-	channel_may_free(channel);
-	return TRUE;
-    }
+	return channel_may_free(channel);
     return FALSE;
 }
 #endif
diff --git a/src/proto/channel.pro b/src/proto/channel.pro
index 8dc4ad44d1..5fd7f1405e 100644
--- a/src/proto/channel.pro
+++ b/src/proto/channel.pro
@@ -4,7 +4,7 @@ int ch_log_active(void);
 void ch_log(channel_T *ch, char *msg);
 void ch_logs(channel_T *ch, char *msg, char *name);
 channel_T *add_channel(void);
-void channel_may_free(channel_T *channel);
+int channel_may_free(channel_T *channel);
 void channel_free(channel_T *channel);
 void channel_gui_register(channel_T *channel);
 void channel_gui_register_all(void);
diff --git a/src/version.c b/src/version.c
index d9697a8f96..86ed223177 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1451,
 /**/
     1450,
 /**/