Shameless plug, I wrote a blog article explaining the yosefk example above more explicitly: <a href="http:&#x2F;&#x2F;blog.reverberate.org&#x2F;2013&#x2F;08&#x2F;parsing-c-is-literally-undecidable.html" rel="nofollow">http:&#x2F;&#x2F;blog.reverberate.org&#x2F;2013&#x2F;08&#x2F;parsing-c-is-literally-u...</a>