Merge pull request #6989 from mself:gftt-deterministic-sort

modules/imgproc/src/featureselect.cpp

@@ -54,7 +54,8 @@ struct greaterThanPtr :
         public std::binary_function<const float *, const float *, bool>
 {
     bool operator () (const float * a, const float * b) const
-    { return *a > *b; }
+    // Ensure a fully deterministic result of the sort
+    { return (*a > *b) ? true : (*a < *b) ? false : (a > b); }
 };
 
 #ifdef HAVE_OPENCL
@@ -66,7 +67,8 @@ struct Corner
     short x;
 
     bool operator < (const Corner & c) const
-    {  return val > c.val; }
+    // Ensure a fully deterministic result of the sort
+    {  return (val > c.val) ? true : (val < c.val) ? false : (y > c.y) ? true : (y < c.y) ? false : (x > c.x); }
 };
 
 static bool ocl_goodFeaturesToTrack( InputArray _image, OutputArray _corners,