diff --git a/geometry.cpp b/geometry.cpp
index ef63cae958..76fa5e3e1e 100644
--- a/geometry.cpp
+++ b/geometry.cpp
@@ -809,7 +809,10 @@ void Workspace::fixPositionAfterCrash(xcb_window_t w, const xcb_get_geometry_rep
     NETStrut frame = i.frameExtents();
 
     if (frame.left != 0 || frame.top != 0) {
-        const uint32_t values[] = { geometry->x - frame.left, geometry->y - frame.top };
+        // left and top needed due to narrowing conversations restrictions in C++11
+        const uint32_t left = frame.left;
+        const uint32_t top = frame.top;
+        const uint32_t values[] = { geometry->x - left, geometry->y - top };
         xcb_configure_window(connection(), w, XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y, values);
     }
 }