Fix some VC type conversion warnings

src/controllers/midi/portmidicontroller.cpp

@@ -218,7 +218,7 @@ void PortMidiController::send(const QByteArray& data) {
     // Pm_WriteSysEx. Instead, it scans for a MIDI_EOX byte to know when the
     // message is over. If one is not provided, it will overflow the buffer and
     // cause a segfault.
-    if (!data.endsWith(MIDI_EOX)) {
+    if (!data.endsWith(static_cast<char>(MIDI_EOX))) {
         controllerDebug("SysEx message does not end with 0xF7 -- ignoring.");
         return;
     }

src/encoder/encoderopus.cpp

@@ -298,7 +298,7 @@ void EncoderOpus::pushTagsPacket() {
     int commentCount = 0;
 
     const char* vendorString = opus_get_version_string();
-    int vendorStringLength = strlen(vendorString);
+    int vendorStringLength = static_cast<int>(strlen(vendorString));
 
     // == Compute tags frame size ==
     // - Magic signature: 8 bytes

src/engine/sync/synccontrol.cpp

@@ -447,7 +447,7 @@ void SyncControl::updateAudible() {
     int channelIndex = m_pChannel->getChannelIndex();
     if (channelIndex >= 0) {
         CSAMPLE_GAIN gain = getEngineMaster()->getMasterGain(channelIndex);
-        bool newAudible = gain > CSAMPLE_GAIN_ZERO;
+        int newAudible = (gain > CSAMPLE_GAIN_ZERO) ? 1 : 0;
         if (m_audible != newAudible) {
             m_audible = newAudible;
             m_pEngineSync->notifyPlayingAudible(this, m_pPlayButton->toBool() && m_audible);

src/waveform/waveformwidgetfactory.cpp

@@ -646,7 +646,7 @@ void WaveformWidgetFactory::render() {
                 // Don't bother doing the pre-render work if we aren't going to
                 // render this widget.
                 bool shouldRender = shouldRenderWaveform(pWaveformWidget);
-                shouldRenderWaveforms[i] = shouldRender;
+                shouldRenderWaveforms[static_cast<int>(i)] = shouldRender;
                 if (!shouldRender) {
                     continue;
                 }
@@ -662,7 +662,7 @@ void WaveformWidgetFactory::render() {
                     i < m_waveformWidgetHolders.size();
                     i++) {
                 WaveformWidgetAbstract* pWaveformWidget = m_waveformWidgetHolders[i].m_waveformWidget;
-                if (!shouldRenderWaveforms[i]) {
+                if (!shouldRenderWaveforms[static_cast<int>(i)]) {
                     continue;
                 }
                 pWaveformWidget->render();

src/widget/wtracktableviewheader.cpp

@@ -49,7 +49,7 @@ HeaderViewState::HeaderViewState(const QString& base64serialized) {
 QString HeaderViewState::saveState() const {
     // Serialize the proto to a byte array, then encode the array as Base64.
 #if GOOGLE_PROTOBUF_VERSION >= 3001000
-    size_t size = m_view_state.ByteSizeLong();
+    int size = static_cast<int>(m_view_state.ByteSizeLong());
 #else
     int size = m_view_state.ByteSize();
 #endif