diff --git a/nc_optimisation.cmake b/nc_optimisation.cmake
index 4502874..3e179d6 100644
--- a/nc_optimisation.cmake
+++ b/nc_optimisation.cmake
@@ -87,7 +87,6 @@ else()
     # clang vectorisation
     append_compile_flag(-fvectorize)
     append_compile_flag(-fslp-vectorize)
-    append_compile_flag(-fslp-vectorize-aggressive)
 
     # loop hosting/distribution
     append_compile_flag(-floop-nest-optimize)