--- mlpack-3.0.4/CMakeLists.txt	2018-11-13 17:33:55.000000000 -0500
+++ mlpack-3.0.4/CMakeLists.txt.b	2019-02-09 00:48:37.707835375 -0500
@@ -190,6 +190,12 @@
   add_definitions(-DARMA_EXTRA_DEBUG)
 endif()
 
+if (LIBDIR)
+  message(STATUS "Setting libdir to ${LIBDIR}.")
+else ()
+  set(LIBDIR "lib")
+endif ()
+
 # Now, find the libraries we need to compile against.  Several variables can be
 # set to manually specify the directory in which each of these libraries
 # resides.
@@ -569,5 +575,5 @@
 
   # Do we need a different directory?
   install(FILES ${CMAKE_CURRENT_BINARY_DIR}/lib/pkgconfig/mlpack.pc
-      DESTINATION lib/pkgconfig/)
+      DESTINATION ${LIBDIR}/pkgconfig/)
 endif ()
--- mlpack-3.0.4/src/mlpack/CMakeLists.txt	2018-11-13 17:33:55.000000000 -0500
+++ mlpack-3.0.4/src/mlpack/CMakeLists.txt.b	2019-02-08 17:11:39.599468186 -0500
@@ -97,8 +97,8 @@
 # be entered...
 install(TARGETS mlpack
   RUNTIME DESTINATION bin
-  LIBRARY DESTINATION lib
-  ARCHIVE DESTINATION lib)
+  LIBRARY DESTINATION ${LIBDIR}
+  ARCHIVE DESTINATION ${LIBDIR})
 
 add_dependencies(mlpack mlpack_headers)