From a0fa63879fedf42b6e0bb342ddc8b2117de7ea70 Mon Sep 17 00:00:00 2001
From: Jeffrey Walton <noloader@gmail.com>
Date: Thu, 3 Jan 2019 19:52:57 -0500
Subject: [PATCH] Add PACK32x4 macro guard

---
 chacha_simd.cpp | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/chacha_simd.cpp b/chacha_simd.cpp
index b7d9c0a9..615a0a55 100644
--- a/chacha_simd.cpp
+++ b/chacha_simd.cpp
@@ -72,11 +72,13 @@ ANONYMOUS_NAMESPACE_BEGIN
 
 // Thanks to Peter Cordes, https://stackoverflow.com/q/54016821/608639
 #if (CRYPTOPP_ARM_NEON_AVAILABLE)
-# if defined(_MSC_VER)
-#  define PACK32x4(w,x,y,z) { ((w) + (word64(x) << 32)), ((y) + (word64(z) << 32)) }
-# else
-#  define PACK32x4(w,x,y,z) { (w), (x), (y), (z) }
-# endif
+# ifndef PACK32x4
+#  if defined(_MSC_VER)
+#   define PACK32x4(w,x,y,z) { ((w) + (word64(x) << 32)), ((y) + (word64(z) << 32)) }
+#  else
+#   define PACK32x4(w,x,y,z) { (w), (x), (y), (z) }
+#  endif
+# endif  // PACK32x4
 #endif  // Microsoft workaround
 
 #if (CRYPTOPP_ARM_NEON_AVAILABLE)