diff --git a/src/app/tools/vabstracttool.cpp b/src/app/tools/vabstracttool.cpp
index 8552290e6..2edf0952c 100644
--- a/src/app/tools/vabstracttool.cpp
+++ b/src/app/tools/vabstracttool.cpp
@@ -34,6 +34,7 @@
 #include "../geometry/vpointf.h"
 #include "../undocommands/savetooloptions.h"
 #include "../widgets/vmaingraphicsview.h"
+#include <QtCore/qmath.h>
 
 const QString VAbstractTool::AttrType        = QStringLiteral("type");
 const QString VAbstractTool::AttrMx          = QStringLiteral("mx");
@@ -205,7 +206,7 @@ qint32 VAbstractTool::LineIntersectCircle(const QPointF &center, qreal radius, c
         }
     }
     // find distance from projection to points of intersection
-    qreal k = sqrt (radius * radius - d * d);
+    qreal k = qSqrt (radius * radius - d * d);
     qreal t = QLineF (QPointF (0, 0), QPointF (b, - a)).length();
     // add to projection a vectors aimed to points of intersection
     p1 = addVector (p, QPointF (0, 0), QPointF (- b, a), k / t);
diff --git a/src/app/visualization/visline.cpp b/src/app/visualization/visline.cpp
index 2adcdc2a5..2cacce052 100644
--- a/src/app/visualization/visline.cpp
+++ b/src/app/visualization/visline.cpp
@@ -99,7 +99,7 @@ QPointF VisLine::Ray(const QPointF &firstPoint, const qreal &angle) const
     line.setAngle(angle);
 
     QRectF scRect = this->scene()->sceneRect();
-    qreal diagonal = sqrt(pow(scRect.height(), 2) + pow(scRect.width(), 2));
+    qreal diagonal = qSqrt(pow(scRect.height(), 2) + pow(scRect.width(), 2));
     line.setLength(diagonal);
     if (QGuiApplication::keyboardModifiers() == Qt::ShiftModifier)
     {