string.c: this assumption is false [ci skip]

Looking at the lines right above, it is clear than a blue sky
that we cannot assume `p` to be aligned at all when
UNALIGNED_WORD_ACCESS is true.  It is a wrong idea to use
__builtin_assume_aligned for that situation.

See also: https://travis-ci.org/ruby/ruby/jobs/451710732#L2007


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65592 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

string.c

@@ -490,7 +490,7 @@ search_nonascii(const char *p, const char *e)
 	    }
 	}
 #endif
-#ifdef HAVE_BUILTIN___BUILTIN_ASSUME_ALIGNED
+#if defined(HAVE_BUILTIN___BUILTIN_ASSUME_ALIGNED) &&! UNALIGNED_WORD_ACCESS
 #define aligned_ptr(value) \
         __builtin_assume_aligned((value), sizeof(uintptr_t))
 #else