diff --git a/Rsconscript b/Rsconscript
index 9746eea..86e2cc8 100644
--- a/Rsconscript
+++ b/Rsconscript
@@ -113,10 +113,8 @@ hulk_env = env "hulk", use: %w[ldc2 x86_64-elf-gcc] do |env|
     -avx512bw
     -avx512cd
     -avx512dq
-    -avx512er
     -avx512f
     -avx512ifma
-    -avx512pf
     -avx512vbmi
     -avx512vbmi2
     -avx512vl