From: fbrosson <fbrosson@users.noreply.github.com>
Date: Fri, 18 May 2018 18:40:11 +0000 (+0000)
Subject: __builtin_prefetch did probably not exist before gcc 3.1.
X-Git-Tag: v1.3.5~3^2~51^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F1139%2Fhead;p=thirdparty%2Fzstd.git

__builtin_prefetch did probably not exist before gcc 3.1.
---

diff --git a/lib/common/compiler.h b/lib/common/compiler.h
index b588e1104..366ed2b4b 100644
--- a/lib/common/compiler.h
+++ b/lib/common/compiler.h
@@ -92,7 +92,7 @@
 #if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_I86))  /* _mm_prefetch() is not defined outside of x86/x64 */
 #  include <mmintrin.h>   /* https://msdn.microsoft.com/fr-fr/library/84szxsww(v=vs.90).aspx */
 #  define PREFETCH(ptr)   _mm_prefetch((const char*)ptr, _MM_HINT_T0)
-#elif defined(__GNUC__)
+#elif defined(__GNUC__) && ( (__GNUC__ >= 4) || ( (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1) ) )
 #  define PREFETCH(ptr)   __builtin_prefetch(ptr, 0, 0)
 #else
 #  define PREFETCH(ptr)   /* disabled */