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by arestor 3403 days ago
It's C. If you have an array, you may only compare to one element behind the last. Everything else is undefined behavior. So a compiler may just "optimize" your >= to ==.
2 comments
eridius 3403 days ago
No it won't. It's using pointers, not array indices. The compiler has no possible way of knowing that `pe` is the one-past-the-end address.
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arestor 3403 days ago
It's still UB. The array could potentially be at the end of the address space...
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eridius 3403 days ago
Well yes, it could, but that's not really an argument for saying that Ragel using == is just as good as using >=.
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vbernat 3403 days ago
It's not an array. It's inside a large buffer allocated by nginx.
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