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Re: No warning on unused variable
>
> Why did this not warn me about the unused stringstream?
[snip]
> it is concievable that declaring this object
> might be sufficient for some action to be taken by the code, thus
> rendering it incorrect for -Wall to report it.
You got it in one. For example, you might see
{
lock myLock;
...
}
where the lock constructor locks memory and the destructor releases
it.
It might be nice if g++ could add an __attribute__ setting so you could
tag a class with something like ctor_has_no_useful_side_effects.
Classes with this attribute could then be allowed to raise the "declared
but not used" warning. It would be most useful on things like
std::string, which you also wouldn't want just laying around.