From 67451cc3e2a05083cdd04127f9662f80ba430474 Mon Sep 17 00:00:00 2001
From: Sean Parkinson <sean@wolfssl.com>
Date: Tue, 14 Nov 2017 11:36:22 +1000
Subject: [PATCH] Fix for older compilers and AVX2

---
 wolfcrypt/src/sha256.c | 15 ++++++++++++++-
 wolfcrypt/src/sha512.c | 16 +++++++++++++++-
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/wolfcrypt/src/sha256.c b/wolfcrypt/src/sha256.c
index ded5ab147..9b237cc0d 100644
--- a/wolfcrypt/src/sha256.c
+++ b/wolfcrypt/src/sha256.c
@@ -92,7 +92,20 @@
 
 #if defined(USE_INTEL_SPEEDUP)
     #define HAVE_INTEL_AVX1
-    #define HAVE_INTEL_AVX2
+
+    #if defined(__GNUC__) && ((__GNUC__ < 4) || \
+                              (__GNUC__ == 4 && __GNUC_MINOR__ <= 8))
+        #define NO_AVX2_SUPPORT
+    #endif
+    #if defined(__clang__) && ((__clang_major__ < 3) || \
+                               (__clang_major__ == 3 && __clang_minor__ <= 5))
+        #define NO_AVX2_SUPPORT
+    #endif
+
+    #define HAVE_INTEL_AVX1
+    #ifndef NO_AVX2_SUPPORT
+        #define HAVE_INTEL_AVX2
+    #endif
 #endif /* USE_INTEL_SPEEDUP */
 
 #if defined(HAVE_INTEL_AVX2)
diff --git a/wolfcrypt/src/sha512.c b/wolfcrypt/src/sha512.c
index 8f112ad23..377f50220 100644
--- a/wolfcrypt/src/sha512.c
+++ b/wolfcrypt/src/sha512.c
@@ -129,7 +129,21 @@
 
 #if defined(USE_INTEL_SPEEDUP)
     #define HAVE_INTEL_AVX1
-    #define HAVE_INTEL_AVX2
+
+
+    #if defined(__GNUC__) && ((__GNUC__ < 4) || \
+                              (__GNUC__ == 4 && __GNUC_MINOR__ <= 8))
+        #define NO_AVX2_SUPPORT
+    #endif
+    #if defined(__clang__) && ((__clang_major__ < 3) || \
+                               (__clang_major__ == 3 && __clang_minor__ <= 5))
+        #define NO_AVX2_SUPPORT
+    #endif
+
+    #define HAVE_INTEL_AVX1
+    #ifndef NO_AVX2_SUPPORT
+        #define HAVE_INTEL_AVX2
+    #endif
 #endif
 
 #if defined(HAVE_INTEL_AVX1)