As long as we are talking about syntactic parsing, this is not a problem as long as the attachment is the same. In both cases 'bread' is the direct object of the main verb.
Of course, there are cases where a particular word can be used both as a direct object and a subject of a particular verb. E.g.:
The man ate the pig.
The pig ate the apple.
Of course, what such systems are learning are not rules, but probability distributions that combine information about the distributions of word orders, association strengths between heads and dependent with a particular dependency relation, configurations of dependent pairs, etc.
Rick: Why haven't we got any bread?
Neil: Because we haven't got any bread.
The point being though, that even if you are taught "Hello, how are you" in an English class then you could well be stumped when you come to my region and we say "How's tricks?"
"We can't buy any bread because we haven't got any bread."
And it's not just English. In Chinese one is taught that "ni hao ma?" is the greeting equivalent to "hello, how are you" but try it on a Chinese person and it amuses them. My Chinese friend at Uni says that Chinese people use "Ni chi ma?" which is literally "have you eaten?" (although we both appreciate that is a bit of a generalisation for 1bn people).