Use DBL_MAX, not arbitrary 1000000000.0, as "infinite" time interval

src/AudioIO.cpp

@@ -269,6 +269,7 @@ writing audio.
 #include "AudioIO.h"
 #include "float_cast.h"
 
+#include <cfloat>
 #include <math.h>
 #include <stdlib.h>
 #include <algorithm>

src/AudioIO.h

@@ -70,7 +70,8 @@ bool ValidateDeviceNames();
 
 class AudioIOListener;
 
-#define BAD_STREAM_TIME -1000000000.0
+// #include <cfloat> if you need this constant
+#define BAD_STREAM_TIME (-DBL_MAX)
 
 #define MAX_MIDI_BUFFER_SIZE 5000
 #define DEFAULT_SYNTH_LATENCY 5

src/Lyrics.cpp

@@ -421,7 +421,7 @@ void Lyrics::Update(double t)
 {
    if (t < 0.0)
    {
-      // TrackPanel::OnTimer passes gAudioIO->GetStreamTime(), which is -1000000000 if !IsStreamActive().
+      // TrackPanel::OnTimer passes gAudioIO->GetStreamTime(), which is -DBL_MAX if !IsStreamActive().
       // In that case, use the selection start time.
       AudacityProject* pProj = GetActiveProject();
       mT = pProj->GetSel0();

src/Menus.cpp

@@ -5888,7 +5888,7 @@ void AudacityProject::HandleAlign(int index, bool moveSel)
    wxString action;
    wxString shortAction;
    double offset;
-   double minOffset = 1000000000.0;
+   double minOffset = DBL_MAX;
    double maxEndOffset = 0.0;
    double leftOffset = 0.0;
    bool bRightChannel = false;

src/MixerBoard.cpp

@@ -13,6 +13,7 @@
 #include "Experimental.h"
 #include "MixerBoard.h"
 
+#include <cfloat>
 #include <math.h>
 
 #include <wx/dcmemory.h>

src/TimeTrack.cpp

@@ -16,6 +16,7 @@
 #include "Audacity.h"
 #include "TimeTrack.h"
 
+#include <cfloat>
 #include <wx/intl.h>
 #include "AColor.h"
 #include "widgets/Ruler.h"
@@ -44,7 +45,7 @@ TimeTrack::TimeTrack(const std::shared_ptr<DirManager> &projDirManager, const Zo
    mDisplayLog = false;
 
    mEnvelope = std::make_unique<Envelope>();
-   mEnvelope->SetTrackLen(1000000000.0);
+   mEnvelope->SetTrackLen(DBL_MAX);
    mEnvelope->SetInterpolateDB(true);
    mEnvelope->Flatten(1.0);
    mEnvelope->Mirror(false);
@@ -71,7 +72,7 @@ TimeTrack::TimeTrack(const TimeTrack &orig):
 
    ///@TODO: Give Envelope:: a copy-constructor instead of this?
    mEnvelope = std::make_unique<Envelope>();
-   mEnvelope->SetTrackLen(1000000000.0);
+   mEnvelope->SetTrackLen(DBL_MAX);
    SetInterpolateLog(orig.GetInterpolateLog()); // this calls Envelope::SetInterpolateDB
    mEnvelope->Flatten(1.0);
    mEnvelope->Mirror(false);

src/toolbars/ControlToolBar.cpp

@@ -33,6 +33,7 @@
 *//*******************************************************************/
 
 #include <algorithm>
+#include <cfloat>
 
 #include "../Audacity.h"
 #include "../Experimental.h"
@@ -891,7 +892,7 @@ void ControlToolBar::OnRecord(wxCommandEvent &evt)
       double t0 = p->GetSel0();
       double t1 = p->GetSel1();
       if (t1 == t0)
-         t1 = 1000000000.0;     // record for a long, long time (tens of years)
+         t1 = DBL_MAX;     // record for a long, long time
 
       /* TODO: set up stereo tracks if that is how the user has set up
        * their preferences, and choose sample format based on prefs */
@@ -985,7 +986,7 @@ void ControlToolBar::OnRecord(wxCommandEvent &evt)
             }
          }
 
-         t1 = 1000000000.0;     // record for a long, long time (tens of years)
+         t1 = DBL_MAX;     // record for a long, long time
       }
       else {
          bool recordingNameCustom, useTrackNumber, useDateStamp, useTimeStamp;