diff --git a/src/plugins/dplatforminterface.cpp b/src/plugins/dplatforminterface.cpp
index f221196..f7d5fd1 100644
--- a/src/plugins/dplatforminterface.cpp
+++ b/src/plugins/dplatforminterface.cpp
@@ -50,12 +50,12 @@ int DPlatformInterface::dndDragThreshold() const
 
 int DPlatformInterface::windowRadius() const
 {
-    return {};
+    return -1;
 }
 
-int DPlatformInterface::windowRadius(int) const
+int DPlatformInterface::windowRadius(int defaultValue) const
 {
-    return {};
+    return defaultValue;
 }
 
 QByteArray DPlatformInterface::themeName() const