TypeLoc of a template class type in an uninstantiated template has incomplete type?

Clang Frontend
#1

Hi all,

I am trying to match type references of class A in the following code:

 template <typename T>
 class A {};


 template <typename T>
 class Temp {
   A<int> a;
   A<T> at;
 };
#2

Hi Eric,

A<T> in class Temp definition is a dependent name (see http://eel.is/c++draft/temp.dep) whereas in class Temp specialization it is not (it is instantiated as A<int>). In case of dependent names, clang will not offer you any additional details about the construct because semantics of such a construct may differ from one instantiation to another.

I had a very similar question few days ago (http://lists.llvm.org/pipermail/cfe-dev/2017-January/052376.html). Although I am not using AST matcher, but rather libclang directly, I did end up implementing heuristic method for extracting the details that I needed and which seems to be quite applicable in my target use-case. I am not sure about your use-case and how flexible AST matcher is but you might want to try to jump to the declaration of dependent-name node and then walk through it to get more details which you need.

Cheers,
Adi

#3

Thank you for the explanation, Jusufadis! I am just trying to see if I can match a class template reference in a template declaration without going into ClassTemplateSpecializationDecl so that I don’t need to worry about parameter substitution. But looks like I have to deal with the substitutions.