g++ fails on qualified name in multiple inheritance

[Michael Tsang]

struct base{
        int x;
        base():x(){}
        virtual~base(){}
};

struct aa:public base{
};

struct ab:public base{
};

struct ba:public aa,ab{
};

struct bb:public aa,ab{
};

struct final:public ba,bb{
};

int main(){
        final obj;
        obj.ba::aa::x=5;
}

/*
Expected behaviour:
The member x accessed by the path final::ba::aa::x in main()::obj is changed to 5

Actual behaviour:
g++ fails to compile this program generating:
test.cpp: In function ‘int main()’:
test.cpp:24: error: ‘aa’ is an ambiguous base of ‘final’
*/

[Matthias Klose (doko)]

See the upstream bug report, this is intended behaviour afaics.

[Michael Tsang (miklcct)]

On Saturday 12 September 2009 21:48:47 Matthias Klose wrote:
> See the upstream bug report, this is intended behaviour afaics.
>
>
> ** Bug watch added: GCC Bugzilla #16889
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16889
>
> ** Also affects: gcc via
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16889
> Importance: Unknown
> Status: Unknown
>
> ** Changed in: gcc-4.4 (Ubuntu)
> Status: New => Incomplete
>

However, the problem is not the same as the upstream report.
If we comment out the line b.f(); , the code compiles.
The upstream report is about member selection without the FQN but in my
program, it even generate errors with the FQN.