"Undefined Behavior in C++; what is it, and why should I care":
https://github.com/boostcon/cppnow_presentations_2014/blob/master/files/Undefined-Behavior.pdf?raw=true
This reminds us to remove as much undefined behavior as possible from D.

Fixing some of those problems will break some D code. An example from the slides pack:

void main() {
    import std.stdio;
    auto arr = [0, 2, 4, 6, 8];
    int i = 1;
    writeln(i + arr[++i] + arr[i++]);
}


It gives different results in dmd and ldc2:

...>dmd -wi -run temp.d
9

...>ldmd2 -wi -run temp.d
10

Hopefully no one writes code like that, but this situation can't be accepted in a language that tries to be safer and better than C/C++.

Bye,
bearophile

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