G++ refuses to template class code, ms compiler is happy

I'm not a c++/template guru and i can't decide if this is really a valid code or i have encountered a gcc bug:

template  struct A {
 void *p;
};
template  struct B : A {
 void *foo() { return p; }
};

g++ says "error: 'p' was not declared in this scope". microsoft's compiler is happy with the same code.

Can anyone help?

1 Answer

Current MSVC in standard C++ mode? That's odd.

The compiler doesn't now the members of A when the B template is compiled. (There might be a partial specialization later in the file.) Therefore, you must explicitly request dependent name lookup by
dereferencing the this pointer:

template  struct B : A {
 void *foo() { return this->p; }
};

answer Jun 14, 2013 by anonymous

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G++ refuses to template class code, ms compiler is happy

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