From 93f6b7f36dba0eed49936dcd014a9cf5941a66ac Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Wed, 20 May 2020 01:51:25 +0200
Subject: [PATCH] Difficult to see how any unprotected write with multiple
 readers could be safe.

---
 src/lib/writer.cc | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/lib/writer.cc b/src/lib/writer.cc
index d346c4a4f..699f220c4 100644
--- a/src/lib/writer.cc
+++ b/src/lib/writer.cc
@@ -777,10 +777,9 @@ Writer::video_reel (int frame) const
 void
 Writer::set_digest_progress (Job* job, float progress)
 {
-	/* I believe this is thread-safe */
-	_digest_progresses[boost::this_thread::get_id()] = progress;
-
 	boost::mutex::scoped_lock lm (_digest_progresses_mutex);
+
+	_digest_progresses[boost::this_thread::get_id()] = progress;
 	float min_progress = FLT_MAX;
 	for (map<boost::thread::id, float>::const_iterator i = _digest_progresses.begin(); i != _digest_progresses.end(); ++i) {
 		min_progress = min (min_progress, i->second);
-- 
2.30.2