https://bugs.gentoo.org/637110

Original patch by Matt Whitlock
Forward-ported from version 2.2.0 to 2.2.2

--- audacity-minsrc-2.2.2-rc1/src/AudioIO.cpp
+++ audacity-minsrc-2.2.2-rc1/src/AudioIO.cpp
@@ -976,6 +976,7 @@
 };
 #endif
 
+#ifdef EXPERIMENTAL_MIDI_OUT
 // return the system time as a double
 static double streamStartTime = 0; // bias system time to small number
 
@@ -995,6 +996,7 @@
 
    return PaUtil_GetTime() - streamStartTime;
 }
+#endif
 
 const int AudioIO::StandardRates[] = {
    8000,
@@ -1803,6 +1805,7 @@
    }
 #endif
 
+#ifdef EXPERIMENTAL_MIDI_OUT
    // We use audio latency to estimate how far ahead of DACS we are writing
    if (mPortStreamV19 != NULL && mLastPaError == paNoError) {
       const PaStreamInfo* info = Pa_GetStreamInfo(mPortStreamV19);
@@ -1811,6 +1814,7 @@
       mAudioOutLatency = info->outputLatency;
       mSystemMinusAudioTimePlusLatency += mAudioOutLatency;
    }
+#endif
 
    return (mLastPaError == paNoError);
 }
@@ -1955,8 +1959,10 @@
 
    double playbackTime = 4.0;
 
+#ifdef EXPERIMENTAL_MIDI_OUT
    streamStartTime = 0;
    streamStartTime = SystemTime(mUsingAlsa);
+#endif
 
 #ifdef EXPERIMENTAL_SCRUBBING_SUPPORT
    bool scrubbing = (options.pScrubbingOptions != nullptr);
@@ -2830,7 +2836,9 @@
 
    mPlaybackTracks.clear();
    mCaptureTracks.clear();
+#ifdef HAVE_MIDI
    mMidiPlaybackTracks.clear();
+#endif
 
 #ifdef EXPERIMENTAL_SCRUBBING_SUPPORT
    mScrubQueue.reset();
@@ -4669,13 +4677,13 @@
          (float *)alloca(framesPerBuffer*numPlaybackChannels * sizeof(float)) :
          (float *)outputBuffer;
 
+#ifdef EXPERIMENTAL_MIDI_OUT
    if (gAudioIO->mCallbackCount++ == 0) {
        // This is effectively mSystemMinusAudioTime when the buffer is empty:
        gAudioIO->mStartTime = SystemTime(gAudioIO->mUsingAlsa) - gAudioIO->mT0;
        // later, mStartTime - mSystemMinusAudioTime will tell us latency
    }
 
-#ifdef EXPERIMENTAL_MIDI_OUT
    /* GSW: Save timeInfo in case MidiPlayback needs it */
    gAudioIO->mAudioCallbackClockTime = PaUtil_GetTime();
 
@@ -5051,7 +5059,9 @@
                   : gAudioIO->mTime >= gAudioIO->mT1))
                   // PRL: singalling MIDI output complete is necessary if
                   // not USE_MIDI_THREAD, otherwise it's harmlessly redundant
+#ifdef EXPERIMENTAL_MIDI_OUT
                   gAudioIO->mMidiOutputComplete = true,
+#endif
                   callbackReturn = paComplete;
             }
             
@@ -5114,7 +5124,9 @@
 
                // PRL: singalling MIDI output complete is necessary if
                // not USE_MIDI_THREAD, otherwise it's harmlessly redundant
+#ifdef EXPERIMENTAL_MIDI_OUT
                gAudioIO->mMidiOutputComplete = true,
+#endif
                callbackReturn = paComplete;
             }
          }
--- audacity-minsrc-2.2.2-rc1/src/Project.cpp
+++ audacity-minsrc-2.2.2-rc1/src/Project.cpp
@@ -460,10 +460,11 @@
          } );
 
          for (const auto &name : sortednames) {
-
+#ifdef USE_MIDI
             if (Importer::IsMidi(name))
                AudacityProject::DoImportMIDI(mProject, name);
             else
+#endif
                mProject->Import(name);
          }
 
@@ -3046,9 +3047,11 @@
 #endif
 
       {
+#ifdef USE_MIDI
          if (Importer::IsMidi(fileName))
             DoImportMIDI(this, fileName);
          else
+#endif
             Import(fileName);
 
          ZoomAfterImport(nullptr);
--- audacity-minsrc-2.2.2-rc1/src/tracks/playabletrack/notetrack/ui/NoteTrackButtonHandle.cpp
+++ audacity-minsrc-2.2.2-rc1/src/tracks/playabletrack/notetrack/ui/NoteTrackButtonHandle.cpp
@@ -9,6 +9,9 @@
 **********************************************************************/
 
 #include "../../../../Audacity.h"
+
+#ifdef USE_MIDI
+
 #include "NoteTrackButtonHandle.h"
 
 #include "../../../../HitTestResult.h"
@@ -113,3 +116,4 @@
    return RefreshCode::RefreshNone;
 }
 
+#endif
--- audacity-minsrc-2.2.2-rc1/src/tracks/playabletrack/notetrack/ui/NoteTrackVZoomHandle.cpp
+++ audacity-minsrc-2.2.2-rc1/src/tracks/playabletrack/notetrack/ui/NoteTrackVZoomHandle.cpp
@@ -9,6 +9,9 @@
 **********************************************************************/
 
 #include "../../../../Audacity.h"
+
+#ifdef USE_MIDI
+
 #include "NoteTrackVZoomHandle.h"
 #include "../../../../Experimental.h"
 #include "NoteTrackVRulerControls.h"
@@ -332,3 +335,5 @@
       TrackVRulerControls::DrawZooming
          ( dc, mRect, panelRect, mZoomStart, mZoomEnd );
 }
+
+#endif
--- audacity-minsrc-2.2.2-rc1/src/tracks/ui/TimeShiftHandle.cpp
+++ audacity-minsrc-2.2.2-rc1/src/tracks/ui/TimeShiftHandle.cpp
@@ -604,7 +604,7 @@
       {
          trySnap = true;
          if (pTrack->GetKind() == Track::Wave) {
-            auto wt = static_cast<const WaveTrack *>(pTrack);
+            auto wt = static_cast<const WaveTrack *>(pTrack.get());
             const double rate = wt->GetRate();
             // set it to a sample point
             desiredSlideAmount = rint(desiredSlideAmount * rate) / rate;