--- a/install_files.cmake
+++ b/install_files.cmake
@@ -4,7 +4,9 @@ set(INSTALL_DATADIR "${CMAKE_INSTALL_PRE
 
 include(CheckTypeSize)
 check_type_size("void*" PTRSIZE)
-if(PTRSIZE EQUAL 8 AND CMAKE_SYSTEM_NAME STREQUAL "Linux")
+if(CMAKE_INSTALL_LIBDIR)
+    set(LIBDIR "${CMAKE_INSTALL_LIBDIR}")
+elseif(PTRSIZE EQUAL 8 AND CMAKE_SYSTEM_NAME STREQUAL "Linux")
     set(LIBDIR "lib64")
 else()
     set(LIBDIR "lib")