diff --git a/src/zxing/zxing/datamatrix/detector/DataMatrixDetector.cpp b/src/zxing/zxing/datamatrix/detector/DataMatrixDetector.cpp
index e33c340..ec2a805 100644
--- a/src/zxing/zxing/datamatrix/detector/DataMatrixDetector.cpp
+++ b/src/zxing/zxing/datamatrix/detector/DataMatrixDetector.cpp
@@ -357,7 +357,7 @@ Ref<ResultPointsAndTransitions> Detector::transitionsBetween(Ref<ResultPoint> fr
   int fromY = (int) from->getY();
   int toX = (int) to->getX();
   int toY = (int) to->getY();
-  bool steep = ::abs(toY - fromY) > abs(toX - fromX);
+  bool steep = ::abs(toY - fromY) > ::abs(toX - fromX);
   if (steep) {
     int temp = fromX;
     fromX = fromY;