marshal.c: fix symlink index

* marshal.c (w_symbol): fix symlink index.  register the given
  symbols, not its name.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46993 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

marshal.c

@@ -422,6 +422,7 @@ w_symbol(VALUE sym, struct dump_arg *arg)
 	w_long((long)num, arg);
     }
     else {
+	const VALUE orig_sym = sym;
 	sym = rb_sym2str(sym);
 	if (!sym) {
 	    rb_raise(rb_eTypeError, "can't dump anonymous ID %"PRIdVALUE, sym);
@@ -436,7 +437,7 @@ w_symbol(VALUE sym, struct dump_arg *arg)
 	}
 	w_byte(TYPE_SYMBOL, arg);
 	w_bytes(RSTRING_PTR(sym), RSTRING_LEN(sym), arg);
-	st_add_direct(arg->symbols, sym, arg->symbols->num_entries);
+	st_add_direct(arg->symbols, orig_sym, arg->symbols->num_entries);
 	if (!NIL_P(encname)) {
 	    struct dump_call_arg c_arg;
 	    c_arg.limit = 1;

test/ruby/test_marshal.rb

@@ -248,6 +248,10 @@ def test_symbol2
     assert_equal(ary, Marshal.load(Marshal.dump(ary)), bug2548)
   end
 
+  def test_symlink
+    assert_include(Marshal.dump([:a, :a]), ';')
+  end
+
   ClassUTF8 = eval("class R\u{e9}sum\u{e9}; self; end")
 
   iso_8859_1 = Encoding::ISO_8859_1