Re: using a class inside a class.

James Kanze <>
Wed, 30 Apr 2008 02:13:37 -0700 (PDT)
On Apr 29, 6:09 pm, wrote:

On Apr 29, 1:46 am, James Kanze <> wrote:


Ahha yes its not C++0x Concepts, its old style concept
checking. Theres bound to be an option to turn that off.
Probbably a macro somewhere

It's off by default (but I always turn it on). To get it, you
need to define _GLIBCXX_CONCEPT_CHECKS, i.e. specify the option


did the default behavior change in gcc 4.3?

I don't know. The latest version I currently have installed
here is 4.1.0. (I really should install 4.3, but I haven't had
time as yet.)

I know that the g++ people are implementing a preliminary
version of concepts, which will change the way this is handled.

i seem to get it by default; and I don't know how to turn it
off. I did try doing a

at the top of the sample app:

---- cut here ----

#include <list>

class CFoo
    std::list<CFoo> m_children;

int main()
    CFoo Foo;
---- cut here ----

But i still get the same error. I would love to be able to
simply disable it if I could...

Just compile with an older version of g++. But why? It will be
a required error in the future, so you won't be able to upgrade
compilers, or us any other more recent compiler, if you do so.
The code is illegal today; it just happens to work with some
compilers, by chance, but even then, the compiler vendor doesn't
guarantee it.

James Kanze (GABI Software)
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