Make sure double to int conversion is correct.

src/conversions.h

Index: src/conversions.h
diff --git a/src/conversions.h b/src/conversions.h
index 70559c9e9d7979f449110793bbdde122cd1d99a5..10c074d4273fbcd792ddb365cb9a61edd67c0a55 100644
--- a/src/conversions.h
+++ b/src/conversions.h
@@ -64,6 +64,8 @@ inline double SignedZero(bool negative) {
 inline int FastD2I(double x) {
   // The static_cast convertion from double to int used to be slow, but

[Sven Panne, 2012/07/30 06:21:46]

I think this comment can be removed, it is totally misleading.

   // as new benchmarks show, now it is much faster than lrint().
+  if (!(x >= INT_MIN)) return INT_MIN;  // Negation to catch NaNs.
+  if (x > INT_MAX) return INT_MAX;
   return static_cast<int>(x);
 }