Re: Cannot understand the following codes

* Ben C:
On 2006-03-28, Alf P. Steinbach <alfps@xxxxxxxx> wrote:
[...]

(*(void (*)
(int,t_go_measurements[]))(stGOFuncs.p_go_Measurements))(i_,ast_);

[...]

What is possibly the type of stGOFuncs.p_go_Measurements? I did not see
its definition.

It's probably a void(*)(). But not matter what type it has, the cast is undefined behavior in C++, and I believe also in C.

Why's it undefined behaviour? I can see that it invites undefined
behaviour, but not that it entails it-- if the value of
stGOFuncs.p_go_Measurements is a function of the correct type won't it
be OK?

It will be OK, /if/ the type is some pointer to function (but not if the type is simply void*, in which case it's UB); I was too hasty there.

Sorry about that... ;-)

--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?
.

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