Fix warnings reported by the pvs-studio team, all inconsequential

src/VoiceKey.cpp

@@ -306,8 +306,15 @@ sampleCount VoiceKey::OnBackward (
          //Initialize these trend markers atrend and ztrend.  They keep track of the
          //up/down trends at the start and end of the evaluation window.
          int atrend = sgn(buffer[remaining - 2]-buffer[remaining - 1]);
+
          int ztrend = sgn(buffer[remaining - WindowSizeInt - 2] -
-                          buffer[remaining - WindowSizeInt - 2]);
+                          buffer[remaining - WindowSizeInt
+                                 // PVS-Studio detected a probable error here
+                                 // when it read - 2.
+                                 // is - 1 correct?
+                                 // This code is unused. I didn't study further.
+                                  - 1
+                           ]);
 
          double erg=0;
          double sc = 0;

src/effects/Equalization.cpp

@@ -369,8 +369,11 @@ bool EffectEqualization::ValidateUI()
 {
    // If editing a batch chain, we don't want to be using the unnamed curve so
    // we offer to save it.
-   while (mDisallowCustom && mCurveName.IsSameAs(wxT("unnamed")))
+
+   if (mDisallowCustom && mCurveName.IsSameAs(wxT("unnamed")))
    {
+      // PRL:  This is unreachable.  mDisallowCustom is always false.
+
       Effect::MessageBox(_("To use this EQ curve in a batch chain, please choose a new name for it.\nChoose the 'Save/Manage Curves...' button and rename the 'unnamed' curve, then use that one."),
          wxOK | wxCENTRE,
          _("EQ Curve needs a different name"));

src/effects/vamp/LoadVamp.cpp

@@ -166,7 +166,7 @@ wxArrayString VampEffectsModule::FindPluginPaths(PluginManagerInterface & WXUNUS
          if (j->sampleType == Plugin::OutputDescriptor::FixedSampleRate ||
                j->sampleType == Plugin::OutputDescriptor::OneSamplePerStep ||
                !j->hasFixedBinCount ||
-               (j->hasFixedBinCount && j->binCount > 1))
+               j->binCount > 1)
          {
             // All of these qualities disqualify (see notes above)
 
@@ -299,7 +299,7 @@ std::unique_ptr<Vamp::Plugin> VampEffectsModule::FindPlugin(const wxString & pat
       if (j->sampleType == Plugin::OutputDescriptor::FixedSampleRate ||
             j->sampleType == Plugin::OutputDescriptor::OneSamplePerStep ||
             !j->hasFixedBinCount ||
-            (j->hasFixedBinCount && j->binCount > 1))
+            j->binCount > 1)
       {
          // All of these qualities disqualify (see notes above)
 

src/export/ExportFFmpeg.cpp

@@ -227,7 +227,7 @@ ExportFFmpeg::ExportFFmpeg()
       SetDescription(ExportFFmpegOptions::fmts[newfmt].Description(), fmtindex);
 
       int canmeta = ExportFFmpegOptions::fmts[newfmt].canmetadata;
-      if (canmeta && (canmeta == AV_VERSION_INT(-1,-1,-1) || canmeta <= avfver))
+      if (canmeta && (canmeta == AV_CANMETA || canmeta <= avfver))
       {
          SetCanMetaData(true,fmtindex);
       }

src/export/ExportFFmpegDialogs.cpp

@@ -1218,11 +1218,11 @@ static wxString iAACProfileNames(int index)
 /// List of export types
 ExposedFormat ExportFFmpegOptions::fmts[] =
 {
-   {FMT_M4A,   wxT("M4A"),    wxT("m4a"), wxT("ipod"), 48,  AV_VERSION_INT(-1,-1,-1), true,  XO("M4A (AAC) Files (FFmpeg)"),         AV_CODEC_ID_AAC,    true},
+   {FMT_M4A,   wxT("M4A"),    wxT("m4a"), wxT("ipod"), 48,  AV_CANMETA,              true,  XO("M4A (AAC) Files (FFmpeg)"),         AV_CODEC_ID_AAC,    true},
    {FMT_AC3,   wxT("AC3"),    wxT("ac3"), wxT("ac3"),  7,   AV_VERSION_INT(0,0,0),    false, XO("AC3 Files (FFmpeg)"),               AV_CODEC_ID_AC3,    true},
    {FMT_AMRNB, wxT("AMRNB"),  wxT("amr"), wxT("amr"),  1,   AV_VERSION_INT(0,0,0),    false, XO("AMR (narrow band) Files (FFmpeg)"), AV_CODEC_ID_AMR_NB, true},
    {FMT_WMA2,  wxT("WMA"),    wxT("wma"), wxT("asf"),  2,   AV_VERSION_INT(52,53,0),  false, XO("WMA (version 2) Files (FFmpeg)"),   AV_CODEC_ID_WMAV2,  true},
-   {FMT_OTHER, wxT("FFMPEG"), wxT(""),    wxT(""),     255, AV_VERSION_INT(-1,-1,-1), true,  XO("Custom FFmpeg Export"),             AV_CODEC_ID_NONE,   true}
+   {FMT_OTHER, wxT("FFMPEG"), wxT(""),    wxT(""),     255, AV_CANMETA,             true,  XO("Custom FFmpeg Export"),             AV_CODEC_ID_NONE,   true}
 };
 
 wxString ExposedFormat::Description() const

src/export/ExportFFmpegDialogs.h

@@ -38,6 +38,8 @@ enum FFmpegExposedFormat
    FMT_LAST
 };
 
+#define AV_CANMETA (AV_VERSION_INT(255, 255, 255))
+
 /// Describes export type
 struct ExposedFormat
 {
@@ -46,7 +48,7 @@ struct ExposedFormat
    const wxChar *extension;   //!< default extension for this format. More extensions may be added later via AddExtension.
    const wxChar *shortname;   //!< used to guess the format
    unsigned maxchannels;      //!< how many channels this format could handle
-   int canmetadata;           //!< !=0 if format supports metadata, -1 any avformat version, otherwise version support added
+   const int canmetadata;           //!< !=0 if format supports metadata, AV_CANMETA any avformat version, otherwise version support added
    bool canutf8;              //!< true if format supports metadata in UTF-8, false otherwise
    const wxChar *description_; //!< format description (will be shown in export dialog) (untranslated!)
    AVCodecID codecid;         //!< codec ID (see libavcodec/avcodec.h)

src/prefs/ExtImportPrefs.cpp

@@ -602,7 +602,8 @@ void ExtImportPrefs::OnDelRule(wxCommandEvent& WXUNUSED(event))
 
    int msgres = AudacityMessageBox (_("Do you really want to delete selected rule?"),
       _("Rule deletion confirmation"), wxYES_NO, RuleTable);
-   if (msgres == wxNO || msgres != wxYES)
+   // Yes or no, there is no third!
+   if (msgres != wxYES)
       return;
 
    RuleTable->DeleteRows (last_selected);

src/widgets/AButton.cpp

@@ -299,12 +299,12 @@ AButton::AButtonState AButton::GetState()
       }
    }
    else {
-      if (mToggle) {
+      //if (mToggle) {
          state = mButtonIsDown ? AButtonDown : AButtonUp;
-      }
+      //}
-      else {
+      //else {
-         state = mButtonIsDown ? AButtonDown : AButtonUp;
+         //state = mButtonIsDown ? AButtonDown : AButtonUp;
-      }
+      //}
    }
 
    return state;

src/widgets/ASlider.cpp

@@ -391,10 +391,10 @@ LWSlider::LWSlider(wxWindow *parent,
       break;
    case DB_SLIDER:
       minValue = -36.0f;
-      if (orientation == wxHORIZONTAL)
+      //if (orientation == wxHORIZONTAL)
          maxValue = 36.0f;
-      else
+      //else
-         maxValue = 36.0f; // for MixerBoard //v Previously was 6dB for MixerBoard, but identical for now.
+         //maxValue = 36.0f; // for MixerBoard //v Previously was 6dB for MixerBoard, but identical for now.
       stepValue = 1.0f;
       speed = 0.5;
       break;

src/widgets/ExpandingToolBar.cpp

@@ -291,10 +291,10 @@ class ExpandingToolBarEvtHandler final : public wxEvtHandler
 
    bool ProcessEvent(wxEvent& evt) override
    {
-      if (mToolBar->IsCursorInWindow())
+//      if (mToolBar->IsCursorInWindow())
-         mToolBar->TryAutoExpand();
-      else
          mToolBar->TryAutoExpand();
+//      else
+//         mToolBar->TryAutoExpand();
 
       return mInheritedEvtHandler->ProcessEvent(evt);
    }

src/widgets/Ruler.cpp

@@ -2427,10 +2427,10 @@ void AdornedRulerPanel::OnMouseEvents(wxMouseEvent &evt)
             // Do this hack so scrubber can detect mouse drags anywhere
             evt.ResumePropagation(wxEVENT_PROPAGATE_MAX);
 
-            if (scrubber.IsScrubbing())
+            //if (scrubber.IsScrubbing())
-               evt.Skip();
-            else
                evt.Skip();
+            //else
+               //evt.Skip();
 
             // Don't do this, it slows down drag-scrub on Mac.
             // Timer updates of display elsewhere make it unnecessary.