disable unaligned word access

* include/ruby/defines.h, st.c: disable unaligned word access with
  gcc 6 or later.  [Bug #11831]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53546 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 4 insertions, 0 deletions

diff --git a/st.c b/st.c
index 9b79704e2c..086ae4d825 100644
--- a/st.c
+++ b/st.c
@@ -1379,6 +1379,10 @@ strhash(st_data_t arg)
 }
 #else
 
+#if !defined(UNALIGNED_WORD_ACCESS) && defined(__GNUC__) && __GNUC__ >= 6
+# define UNALIGNED_WORD_ACCESS 0
+#endif
+
 #ifndef UNALIGNED_WORD_ACCESS
 # if defined(__i386) || defined(__i386__) || defined(_M_IX86) || \
      defined(__x86_64) || defined(__x86_64__) || defined(_M_AMD64) || \