diff --git a/libsharp/sharp_vecsupport.h b/libsharp/sharp_vecsupport.h
index 942e290..914a899 100644
--- a/libsharp/sharp_vecsupport.h
+++ b/libsharp/sharp_vecsupport.h
@@ -112,9 +112,6 @@ static inline Tv vblend__(Tv m, Tv a, Tv b)
 #if (VLEN==4)
 
 #include <immintrin.h>
-#if (USE_FMA4)
-#include <x86intrin.h>
-#endif
 
 typedef __m256d Tv;
 typedef __m256d Tm;
diff --git a/libsharp/sharp_vecutil.h b/libsharp/sharp_vecutil.h
index 522cc5f..e872bb3 100644
--- a/libsharp/sharp_vecutil.h
+++ b/libsharp/sharp_vecutil.h
@@ -34,7 +34,7 @@
 
 #ifndef VLEN
 
-#if (defined (__MIC__))
+#if (defined (__MIC__) || defined(__AVX512F__))
 #define VLEN 8
 #elif (defined (__AVX__))
 #define VLEN 4
@@ -46,12 +46,4 @@
 
 #endif
 
-#ifndef USE_FMA4
-#ifdef __FMA4__
-#define USE_FMA4 1
-#else
-#define USE_FMA4 0
-#endif
-#endif
-
 #endif