diff --git a/Eigen/src/Core/arch/AVX512/PacketMath.h b/Eigen/src/Core/arch/AVX512/PacketMath.h
index 4832f2a3b..a2c9599b6 100644
--- a/Eigen/src/Core/arch/AVX512/PacketMath.h
+++ b/Eigen/src/Core/arch/AVX512/PacketMath.h
@@ -263,18 +263,18 @@ EIGEN_STRONG_INLINE Packet8d pmax<Packet8d>(const Packet8d& a,
 }
 
 #ifdef EIGEN_VECTORIZE_AVX512DQ
-template<int I> EIGEN_STRONG_INLINE Packet8f extract256(Packet16f x) { return _mm512_extractf32x8_ps(x,I); }
-template<int I> EIGEN_STRONG_INLINE Packet2d extract128(Packet8d x) { return _mm512_extractf64x2_pd(x,I); }
+template<int I_> EIGEN_STRONG_INLINE Packet8f extract256(Packet16f x) { return _mm512_extractf32x8_ps(x,I_); }
+template<int I_> EIGEN_STRONG_INLINE Packet2d extract128(Packet8d x) { return _mm512_extractf64x2_pd(x,I_); }
 EIGEN_STRONG_INLINE Packet16f cat256(Packet8f a, Packet8f b) { return _mm512_insertf32x8(_mm512_castps256_ps512(a),b,1); }
 #else
 // AVX512F does not define _mm512_extractf32x8_ps to extract _m256 from _m512
-template<int I> EIGEN_STRONG_INLINE Packet8f extract256(Packet16f x) {
-  return  _mm256_castsi256_ps(_mm512_extracti64x4_epi64( _mm512_castps_si512(x),I));
+template<int I_> EIGEN_STRONG_INLINE Packet8f extract256(Packet16f x) {
+  return  _mm256_castsi256_ps(_mm512_extracti64x4_epi64( _mm512_castps_si512(x),I_));
 }
 
 // AVX512F does not define _mm512_extractf64x2_pd to extract _m128 from _m512
-template<int I> EIGEN_STRONG_INLINE Packet2d extract128(Packet8d x) {
-  return _mm_castsi128_pd(_mm512_extracti32x4_epi32( _mm512_castpd_si512(x),I));
+template<int I_> EIGEN_STRONG_INLINE Packet2d extract128(Packet8d x) {
+  return _mm_castsi128_pd(_mm512_extracti32x4_epi32( _mm512_castpd_si512(x),I_));
 }
 
 EIGEN_STRONG_INLINE Packet16f cat256(Packet8f a, Packet8f b) {