[cfe-commits] [Patch][Review request] RecursiveASTVisitor can now traverse template specializations

[John McCall]

On Aug 30, 2010, at 2:27 PM, Benoit Belley wrote:
> Thanks for taking the time to review my changes. The following patch should address all of your concerns. I have clarified that I want to traverse all of the template instantiations (not just the explicit ones).
> 
>  /// This visitor always recurses in the declarator of explicit
>  /// template instantiations, such as for example "template class
>  /// set<int>'. But by default, it will not recurse in the
>  /// instantiations (implicit or explicit) of the template (function or
>  /// class) themselves since the instatiated AST isn't written in the
>  /// source code anywhere. This behavior can be changed by overriding
>  /// shouldVisitTemplateInstantiations() in the derived class to return
>  /// true.
> 
> Unfortunately, while testing my changes, I have come across an issue and I don’t know what the correct solution is. The following code snippet (inspired from the Intel TBB header files) demonstrates the issue:
> 
> 
> —————————————————
> // This is fine.
> class A 
> {
>    friend class A;
> }
> 
> // This class template definiton is also fine...
> template<typename Container>
> class vector_iterator
> {
>    template <typename C> friend class vector_iterator;
> };
> 
> // ... until it gets instantiated.
> vector_iterator<int> it_int;
> --------------------------------
> 
> It will throw the RecursiveASTVisitor in an infinite loop when shouldVisitTemplateInstantiations() == true. The attached file tracing.txt contains a trace of the visitor in action and points out to cause of the problem:

Probably you should only visit the instantiations for the template definition.

John.