diff --git a/blake2-simd.cpp b/blake2-simd.cpp
index f1297a72..bd6ffb84 100644
--- a/blake2-simd.cpp
+++ b/blake2-simd.cpp
@@ -28,21 +28,21 @@
 # define EXCEPTION_EXECUTE_HANDLER 1
 #endif
 
+NAMESPACE_BEGIN(CryptoPP)
+
 // Sun Studio 12.3 and earlier lack SSE2's _mm_set_epi64x. Win32 lacks _mm_set_epi64x, Win64 supplies it except for VS2008.
 // Also see http://stackoverflow.com/a/38547909/608639
 #if CRYPTOPP_SSE2_AVAILABLE && ((__SUNPRO_CC >= 0x5100 && __SUNPRO_CC < 0x5130) || (defined(_MSC_VER) && _MSC_VER < 1600) || (defined(_M_IX86) && _MSC_VER >= 1600))
 inline __m128i MM_SET_EPI64X(const word64 a, const word64 b)
 {
     const word64 t[2] = {b,a}; __m128i r;
-    memcpy(&r, &t, sizeof(t));
+    ::memcpy(&r, &t, sizeof(t));
     return r;
 }
 #else
 # define MM_SET_EPI64X(a, b) _mm_set_epi64x(a, b)
 #endif
 
-NAMESPACE_BEGIN(CryptoPP)
-
 ANONYMOUS_NAMESPACE_BEGIN
 
 CRYPTOPP_ALIGN_DATA(16)