string.c: use raw macro

* string.c (str_new_frozen): use raw macro for RString object.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@52070 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

string.c

@@ -1025,7 +1025,7 @@ str_new_frozen(VALUE klass, VALUE orig)
 	str = str_new(klass, RSTRING_PTR(orig), RSTRING_LEN(orig));
     }
     else {
-	if (FL_TEST(orig, STR_SHARED)) {
+	if (FL_TEST_RAW(orig, STR_SHARED)) {
 	    VALUE shared = RSTRING(orig)->as.heap.aux.shared;
 	    long ofs = RSTRING(orig)->as.heap.ptr - RSTRING(shared)->as.heap.ptr;
 	    long rest = RSTRING(shared)->as.heap.len - ofs - RSTRING(orig)->as.heap.len;