DeVault: Announcing the Hare programming language

> remove the "*sum = 0;" line (which tells the compiler it can ignore the subsequent NULL checks).

I don't think that example demonstrates a case for "derferencing NULL is undefined behaviour". The compiled code has the "if (!sum)" hoisted out of the loop, and once you do that optimisation the loop is no different than if the check where completely removed. Seems to me like the reason for the failed vectorisation is more an internal compiler issue, possibly because of the ordering of passes and not because "dereferencing NULL being undefined behaviour" is vital to the vectorisation.