1 files changed, 9 insertions, 10 deletions
diff --git a/src/gui/painting/qpainterpath.cpp b/src/gui/painting/qpainterpath.cpp
index e3c6eabbc3..e2f267d7ee 100644
--- a/src/gui/painting/qpainterpath.cpp
+++ b/src/gui/painting/qpainterpath.cpp
@@ -521,7 +521,7 @@ void QPainterPath::setElementPositionAt(int i, qreal x, qreal y)
 /*!
     Constructs an empty QPainterPath object.
 */
-QPainterPath::QPainterPath()
+QPainterPath::QPainterPath() Q_DECL_NOEXCEPT
     : d_ptr(0)
 {
 }
@@ -3057,20 +3057,19 @@ qreal QPainterPath::slopeAtPercent(qreal t) const
     //tangent line
     qreal slope = 0;
 
-#define SIGN(x) ((x < 0)?-1:1)
     if (m1)
         slope = m2/m1;
     else {
-        //windows doesn't define INFINITY :(
-#ifdef INFINITY
-        slope = INFINITY*SIGN(m2);
-#else
-        if (sizeof(qreal) == sizeof(double)) {
-            return 1.79769313486231570e+308;
+        if (std::numeric_limits<qreal>::has_infinity) {
+            slope = (m2  < 0) ? -std::numeric_limits<qreal>::infinity()
+                              : std::numeric_limits<qreal>::infinity();
         } else {
-            return ((qreal)3.40282346638528860e+38);
+            if (sizeof(qreal) == sizeof(double)) {
+                return 1.79769313486231570e+308;
+            } else {
+                return ((qreal)3.40282346638528860e+38);
+            }
         }
-#endif
     }
 
     return slope;