如果按resident填1040并按treaty要求免税呢（负数+8833）

正常来说treaty不适用于residents，但是84年treaty的protocol 1的第二段如下：
2. Notwithstanding any provision of the Agreement, the United States may tax its citizens. Except as provided in paragraph 2 of Article 8, paragraph 2 of Article 17, and Articles 18, 19, 20, 22, 23, 24 and 26 of this Agreement, the United States may tax its residents (as determined under Article 4).
其中articles 19/20是放在例外里的。
按道理应该还是可以要求免税阿


并且IRS的Technical Explanation在articles 19/20里都提到了：
This article is excepted from the "saving clause" of paragraph 2 of the Protocol, so its
benefits are available to persons who otherwise qualify even if they become U.S. residents.
明确指出即使是resident也可以适用treaty的

treaty原文及解释的链接
http://www.irs.gov/businesses/international/article/0,,id=169483,00.html