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

0 votes

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?

posted Jun 14, 2013 by anonymous

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1 Answer

+1 vote

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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0 votes

This code compiles on MSVC but not on G++ :

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The error with g++ is :

test.cpp: In static member function "static void B::SomeMethod()":
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Is there is a option to indicate to g++ to evaluate the template functions only when a specialization is called, and not before ?

–1 vote

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 namespace t {

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 int i;

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