--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -33,15 +33,9 @@
 
 SET(CMAKE_VERBOSE_MAKEFILE "false")
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/CMake/")
-INCLUDE (GNUInstallDirs OPTIONAL)
-# support old CMake without GNUInstallDirs
-if (NOT CMAKE_INSTALL_FULL_LIBDIR)
-  set (CMAKE_INSTALL_FULL_LIBDIR "${CMAKE_INSTALL_PREFIX}/lib")
-  set (CMAKE_INSTALL_FULL_DATADIR "${CMAKE_INSTALL_PREFIX}/share")
-  set (BEIGNET_LIBRARY_ARCHITECTURE "")
-else (NOT CMAKE_INSTALL_FULL_LIBDIR)
-  set (BEIGNET_LIBRARY_ARCHITECTURE "${CMAKE_LIBRARY_ARCHITECTURE}")
-endif (NOT CMAKE_INSTALL_FULL_LIBDIR)
+set (CMAKE_INSTALL_FULL_LIBDIR "${CMAKE_INSTALL_PREFIX}/lib")
+set (CMAKE_INSTALL_FULL_DATADIR "${CMAKE_INSTALL_PREFIX}/share")
+set (BEIGNET_LIBRARY_ARCHITECTURE "")
 
 if (NOT LIB_INSTALL_DIR)
   set (LIB_INSTALL_DIR "${CMAKE_INSTALL_FULL_LIBDIR}")