default template args in a typedef

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2 total messages Started by Tim Hollebeek Mon, 19 Feb 1996 02:23

#3475

Author: Tim Hollebeek
Date: Mon, 19 Feb 1996 02:23

35 lines
1471 bytes

Is this legal?

-------
template <class T>
class X {
};

template <class T, class U = X<T> >
class Y {
};

typedef Y<double, X<double> > Z1;
typedef Y<double> Z2;

int main() {
    Z1 z1;
    Z2 z2; // <--- here
}
-------

g++ 2.7.2 doesn't mind Z1, but gives:

aggregate `Y<...> z2' has incomplete type and cannot be initialized

on the Z2 line.

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Tim Hollebeek      | Disclaimer :=> Everything above is a true statement,
<space for rent>   |                for sufficiently false values of true.
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Re: default template args in a typedef

#3376

Author: Jason Merrill
Date: Tue, 20 Feb 1996 18:56

37 lines
1606 bytes

>>>>> Tim Hollebeek <tim@franck.Princeton.EDU> writes:

> Is this legal?
> -------
> template <class T>
> class X {
> };

> template <class T, class U = X<T> >
> class Y {
> };

> typedef Y<double, X<double> > Z1;
> typedef Y<double> Z2;

> int main() {
>     Z1 z1;
>     Z2 z2; // <--- here
> }
> -------

> g++ 2.7.2 doesn't mind Z1, but gives:

> aggregate `Y<...> z2' has incomplete type and cannot be initialized

> on the Z2 line.

This is a bug in g++ 2.7.2.

Jason
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