Description: Fix infinite loop with cyclic plugin routing
 See https://lib.openmpt.org/libopenmpt/md_announce-2017-06-02.html
Origin: upstream, https://source.openmpt.org/browse/openmpt?op=revision&rev=8236
Bug-Debian: https://bugs.debian.org/864195
---
This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
--- a/soundlib/Fastmix.cpp
+++ b/soundlib/Fastmix.cpp
@@ -597,10 +597,11 @@ void CSoundFile::ProcessPlugins(uint32 n
 					// Samples or plugins are being rendered, so turn off auto-bypass for this master effect.
 					if(plugin.pMixPlugin != nullptr) plugin.pMixPlugin->ResetSilence();
 					SNDMIXPLUGIN *chain = &plugin;
-					PLUGINDEX out = chain->GetOutputPlugin();
-					while(out > plug && out < MAX_MIXPLUGINS)
+					PLUGINDEX out = chain->GetOutputPlugin(), prevOut = plug;
+					while(out > prevOut && out < MAX_MIXPLUGINS)
 					{
 						chain = &m_MixPlugins[out];
+						prevOut = out;
 						out = chain->GetOutputPlugin();
 						if(chain->pMixPlugin)
 						{