On Sunday, 2 February 2014 at 10:58:51 UTC, Dicebot wrote:
On Sunday, 2 February 2014 at 03:45:06 UTC, Andrei Alexandrescu
wrote:
On 2/1/14, 7:35 PM, deadalnix wrote:
http://blog.llvm.org/2011/05/what-every-c-programmer-should-know_14.html
Whoa, thanks. So the compiler figures null pointer dereference
in C is undefined behavior, which means the entire program
could do whatever if that does happen.
Andrei
As far as I have understood previous posts, it is even worse
than that - LLVM optimiser assumes that C semantics whatever
high-level language is.
deadalnix is that true?
It depends. For instance you can specify semantic of wrap around,
so both undefined and defined overflow exists.
In the precise case we are talking about about, that really do
not make any sense to propose any other semantic as it would
prevent the optimizer to optimize away most load.
