diff --git a/clang/lib/Headers/avx512fintrin.h b/clang/lib/Headers/avx512fintrin.h
index 2877d70..35972f7 100644
--- a/clang/lib/Headers/avx512fintrin.h
+++ b/clang/lib/Headers/avx512fintrin.h
@@ -4229,6 +4229,18 @@
                   _MM_FROUND_CUR_DIRECTION);
 }
 
+static __inline__ double __DEFAULT_FN_ATTRS
+_mm512_cvtsd_f64(__m512d __a)
+{
+  return __a[0];
+}
+
+static __inline__ float __DEFAULT_FN_ATTRS
+_mm512_cvtss_f32(__m512 __a)
+{
+  return __a[0];
+}
+
 /* Unpack and Interleave */
 
 static __inline __m512d __DEFAULT_FN_ATTRS