diff --git a/src/app/gps/qwtpolar-1.0/qwt_polar_curve.cpp b/src/app/gps/qwtpolar-1.0/qwt_polar_curve.cpp
index d63206af799..7c187777dcb 100644
--- a/src/app/gps/qwtpolar-1.0/qwt_polar_curve.cpp
+++ b/src/app/gps/qwtpolar-1.0/qwt_polar_curve.cpp
@@ -433,7 +433,7 @@ void QwtPolarCurve::drawLines( QPainter *painter,
 
     if ( !clipRect.isEmpty() )
     {
-        double off = qCeil( qMax( 1.0, painter->pen().widthF() ) );
+        double off = qCeil( qMax((qreal)1.0,painter->pen().widthF() ) );
         clipRect = clipRect.toRect().adjusted( -off, -off, off, off );
         polyline = QwtClipper::clipPolygonF( clipRect, polyline );
     }
diff --git a/src/app/gps/qwtpolar-1.0/qwt_polar_layout.cpp b/src/app/gps/qwtpolar-1.0/qwt_polar_layout.cpp
index 1db237977f8..b4a43b0e4c4 100644
--- a/src/app/gps/qwtpolar-1.0/qwt_polar_layout.cpp
+++ b/src/app/gps/qwtpolar-1.0/qwt_polar_layout.cpp
@@ -278,7 +278,7 @@ QRectF QwtPolarLayout::layoutLegend( Options options, QRectF &rect ) const
         // We don't allow vertical legends to take more than
         // half of the available space.
 
-        dim = qMin( hint.width(), rect.width() * d_data->legendRatio );
+        dim = qMin( hint.width(), (qreal)(rect.width() * d_data->legendRatio) );
 
         if ( !( options & IgnoreScrollbars ) )
         {
@@ -293,7 +293,7 @@ QRectF QwtPolarLayout::layoutLegend( Options options, QRectF &rect ) const
     }
     else
     {
-        dim = qMin( hint.height(), rect.height() * d_data->legendRatio );
+        dim = qMin( hint.height(), (qreal)(rect.height() * d_data->legendRatio) );
         dim = qMax( dim, d_data->layoutData.legend.hScrollBarHeight );
     }