diff -up extra-cmake-modules-5.47.0/kde-modules/KDEInstallDirs.cmake.qt_prefix extra-cmake-modules-5.47.0/kde-modules/KDEInstallDirs.cmake
--- extra-cmake-modules-5.47.0/kde-modules/KDEInstallDirs.cmake.qt_prefix	2018-05-31 03:10:15.000000000 -0500
+++ extra-cmake-modules-5.47.0/kde-modules/KDEInstallDirs.cmake	2018-06-02 15:41:25.948999508 -0500
@@ -461,7 +461,7 @@ include("${ECM_MODULE_DIR}/ECMQueryQmake
 set(_default_KDE_INSTALL_USE_QT_SYS_PATHS OFF)
 if(NOT DEFINED KDE_INSTALL_USE_QT_SYS_PATHS)
     query_qmake(qt_install_prefix_dir QT_INSTALL_PREFIX TRY)
-    if(qt_install_prefix_dir STREQUAL "${CMAKE_INSTALL_PREFIX}")
+    if( (qt_install_prefix_dir STREQUAL "${CMAKE_INSTALL_PREFIX}") OR ( ("${CMAKE_INSTALL_PREFIX}" STREQUAL "/usr") AND (qt_install_prefix_dir STREQUAL "${CMAKE_INSTALL_FULL_LIBDIR}/qt5")) )
         message(STATUS "Installing in the same prefix as Qt, adopting their path scheme.")
         set(_default_KDE_INSTALL_USE_QT_SYS_PATHS ON)
     endif()