diff --git a/effects/slidingpopups/slidingpopups.cpp b/effects/slidingpopups/slidingpopups.cpp
--- a/effects/slidingpopups/slidingpopups.cpp
+++ b/effects/slidingpopups/slidingpopups.cpp
@@ -152,7 +152,7 @@
                 data.quads = data.quads.splitAtX(splitPoint);
                 WindowQuadList filtered;
                 filtered.reserve(data.quads.count());
-                foreach (const WindowQuad &quad, data.quads) {
+                for (const WindowQuad &quad : qAsConst(data.quads)) {
                     if (quad.left() >= splitPoint) {
                         filtered << quad;
                     }
@@ -165,7 +165,7 @@
                 data.quads = data.quads.splitAtY(splitPoint);
                 WindowQuadList filtered;
                 filtered.reserve(data.quads.count());
-                foreach (const WindowQuad &quad, data.quads) {
+                for (const WindowQuad &quad : qAsConst(data.quads)) {
                     if (quad.top() >= splitPoint) {
                         filtered << quad;
                     }
@@ -178,7 +178,7 @@
                 data.quads = data.quads.splitAtX(splitPoint);
                 WindowQuadList filtered;
                 filtered.reserve(data.quads.count());
-                foreach (const WindowQuad &quad, data.quads) {
+                for (const WindowQuad &quad : qAsConst(data.quads)) {
                     if (quad.right() <= splitPoint) {
                         filtered << quad;
                     }
@@ -192,7 +192,7 @@
                 data.quads = data.quads.splitAtY(splitPoint);
                 WindowQuadList filtered;
                 filtered.reserve(data.quads.count());
-                foreach (const WindowQuad &quad, data.quads) {
+                for (const WindowQuad &quad : qAsConst(data.quads)) {
                     if (quad.bottom() <= splitPoint) {
                         filtered << quad;
                     }