There is no height greater than unconstrained height, bug 402872, r/sr=roc a=beltzner

gfx/public/nsCoord.h

@@ -220,6 +220,29 @@ NSCoordSaturatingSubtract(nscoord a, nscoord b,
   }
 #endif
 }
+/** compare against a nscoord "b", which might be unconstrained
+  * "a" must not be unconstrained.
+  * Every number is smaller than a unconstrained one
+  */
+inline PRBool
+NSCoordLessThan(nscoord a,nscoord b)
+{
+  NS_ASSERTION(a != nscoord_MAX, 
+               "This coordinate should be constrained");
+  return ((a < b) || (b == nscoord_MAX));
+}
+
+/** compare against a nscoord "b", which might be unconstrained
+  * "a" must not be unconstrained
+  * No number is larger than a unconstrained one.
+  */
+inline PRBool
+NSCoordGreaterThan(nscoord a,nscoord b)
+{
+  NS_ASSERTION(a != nscoord_MAX, 
+               "This coordinate should be constrained");
+  return ((a > b) && (b != nscoord_MAX));
+}
 
 /**
  * Convert an nscoord to a PRInt32. This *does not* do rounding because

layout/generic/nsBlockReflowState.cpp

@@ -635,7 +635,7 @@ nsBlockReflowState::CanPlaceFloat(const nsSize& aFloatSize,
   // At this point we know that there is enough horizontal space for
   // the float (somewhere). Lets see if there is enough vertical
   // space.
-  if (mAvailSpaceRect.height < aFloatSize.height) {
+  if (NSCoordGreaterThan(aFloatSize.height, mAvailSpaceRect.height)) {
     // The available height is too short. However, its possible that
     // there is enough open space below which is not impacted by a
     // float.