nixpkgs/pkgs/development/libraries/armadillo/use-unix-config-on-OS-X.patch

--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -84,7 +84,7 @@ message(STATUS "DETECT_HDF5                = ${DETECT_HDF5}"               )
 ##
 ## Find LAPACK and BLAS libraries, or their optimised versions
 ##
-
+set(APPLE false)
 if(APPLE)
   
   set(ARMA_OS macos)