From c78d83c56bdec4935efd7a7d2f758165873d1137 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Wed, 29 Aug 2018 01:24:28 +0100
Subject: [PATCH] Add some asserts.

---
 src/lib/writer.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/lib/writer.cc b/src/lib/writer.cc
index 8e2079aeb..da1a07683 100644
--- a/src/lib/writer.cc
+++ b/src/lib/writer.cc
@@ -678,12 +678,16 @@ Writer::write (PlayerText text, TextType type, optional<DCPTextTrack> track, DCP
 		reel = &_subtitle_reel;
 		break;
 	case TEXT_CLOSED_CAPTION:
+		DCPOMATIC_ASSERT (track);
+		DCPOMATIC_ASSERT (_caption_reels.find(*track) != _caption_reels.end());
 		reel = &_caption_reels[*track];
 		break;
 	default:
 		DCPOMATIC_ASSERT (false);
 	}
 
+
+	DCPOMATIC_ASSERT (*reel != _reels.end());
 	while ((*reel)->period().to <= period.from) {
 		++(*reel);
 		DCPOMATIC_ASSERT (*reel != _reels.end());
-- 
2.30.2