[Bug c++/11750] New: Incorrect virtual method invoked for class hierarchy w/ virtual bases

["jfischer_5809 at yahoo dot com" <gcc-bugzilla at gcc dot gnu dot org>]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11750

           Summary: Incorrect virtual method invoked for class hierarchy w/
                    virtual bases
           Product: gcc
           Version: 3.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jfischer_5809 at yahoo dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu

Paragraph 10.3/2 in the C++ standard [ISO/IEC 14882:1998] provides the following
code example:

<quote>

struct A {
    virtual void f();
};
struct B : virtual A {
    virtual void f();
};

struct C : B , virtual A {
    using A::f; 
};
void foo() {
    C c; 
    c.f();      // calls B::f, the final overrider
    c.C::f();   // calls A::f because of the using-declaration
}

</quote>

When a similar program is compiled using G++ 3.3, the method call 'c.f()' in
function foo() incorrectly invokes A::f and not B::f as specified in the standard.

<example>
<code main.cpp>
#include <iostream>

struct A {
    virtual void f() { std::cout << "A::f()\n"; }
};
struct B : virtual A {
    virtual void f() { std::cout << "B::f()\n"; }
};
struct C : B, virtual A {
    using A::f;
};

int main()
{
    C c;
    c.f();      // ERROR - Incorrectly invokes A::f
    c.C::f();   // OK - Invokes A::f
}
</code>

<build>
$ g++ main.cpp

$ ldd a.out
        libstdc++.so.5 =>
/usr/local/gcc/3.3/lib/gcc-lib/i686-pc-linux-gnu/3.3/libstdc++.so.5 (0x40017000)
        libm.so.6 => /lib/tls/libm.so.6 (0x400e4000)
        libgcc_s.so.1 =>
/usr/local/gcc/3.3/lib/gcc-lib/i686-pc-linux-gnu/3.3/libgcc_s.so.1 (0x40106000)
        libc.so.6 => /lib/tls/libc.so.6 (0x42000000)
        /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)
</build>

<output>
$ ./a.out
A::f()
A::f()
</output>

</example>