From: Yann Collet <cyan@fb.com>
Date: Sat, 24 Mar 2018 01:45:42 +0000 (-0700)
Subject: make DYNAMIC_BMI2 support of clang conditional to __has_attribute()
X-Git-Tag: v1.3.4~1^2~5^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=52ca7c6c565579bfc732184597a30fa904656493;p=thirdparty%2Fzstd.git

make DYNAMIC_BMI2 support of clang conditional to __has_attribute()

to support older clang versions such as 3.4
---

diff --git a/lib/common/compiler.h b/lib/common/compiler.h
index bb8730126..a6044c861 100644
--- a/lib/common/compiler.h
+++ b/lib/common/compiler.h
@@ -74,7 +74,7 @@
  * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
  */
 #ifndef DYNAMIC_BMI2
-  #if defined(__clang__)    \
+  #if (defined(__clang__) && __has_attribute(__target__)) \
       || (defined(__GNUC__) \
           && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))) \
       && (defined(__x86_64__) || defined(_M_X86)) \