From 443535a54cdae125d0e56a82268740893f2e9d6f Mon Sep 17 00:00:00 2001
From: tildearrow <me@tildearrow.org>
Date: Tue, 20 Jun 2023 01:08:51 -0500
Subject: [PATCH] fix possible hang in runMidiClock

issue #1167
---
 src/engine/playback.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/engine/playback.cpp b/src/engine/playback.cpp
index c2397d1e..83c0d29f 100644
--- a/src/engine/playback.cpp
+++ b/src/engine/playback.cpp
@@ -1564,8 +1564,10 @@ void DivEngine::runMidiClock(int totalCycles) {
     if (speedSum<1.0) speedSum=1.0;
     if (vD<1) vD=1;
     double bpm=((24.0*divider)/(timeBase*hl*speedSum))*(double)curSubSong->virtualTempoN/vD;
+    if (bpm<1.0) bpm=1.0;
+    int increment=got.rate*pow(2,MASTER_CLOCK_PREC)/(bpm);
 
-    midiClockCycles+=got.rate*pow(2,MASTER_CLOCK_PREC)/(bpm);
+    midiClockCycles+=increment;
     midiClockDrift+=fmod(got.rate*pow(2,MASTER_CLOCK_PREC),(double)(bpm));
     if (midiClockDrift>=(bpm)) {
       midiClockDrift-=(bpm);