virtual dtors should be non-inline

src/effects/TimeWarper.cpp

@@ -21,6 +21,8 @@ Geometric TimeWarper classes
 #include <wx/string.h>
 #include <math.h>
 
+TimeWarper::~TimeWarper() = default;
+
 double IdentityTimeWarper::Warp(double originalTime) const
 {
    return originalTime;

src/effects/TimeWarper.h

@@ -61,7 +61,7 @@ of the warped region.
 class TimeWarper /* not final */
 {
 public:
-   virtual ~TimeWarper() { }
+   virtual ~TimeWarper();
    virtual double Warp(double originalTime) const = 0;
 };