Heuristic resolution does not find method in base class referenced via alias template

[HighCommander4]

In the following code:

struct Waldo {
  void find();
};

template <typename T>
using Wally = Waldo;

template <typename>
struct S : Wally<int> {
  void Foo() { this->find(); }
};

go-to-definition on the use of find() does not produce Waldo:find() as a result.

[HighCommander4]

This needs to be fixed in the implementation of CXXRecordDecl::lookupDependentName().

I note that CXXRecordDecl::lookupDependentName() does "heuristic resolution" things much like HeuristicResolver (which uses lookupDependentName()). These two pieces of code would benefit from being "at the same level", so that e.g. the implementation of lookupDependentName() can call into other HeuristicResolver functionality.

[HighCommander4]

These two pieces of code would benefit from being "at the same level", so that e.g. the implementation of lookupDependentName() can call into other HeuristicResolver functionality.

Upstreaming HeuristicResolver to live in clang/lib/, as proposed in #1662, would address this.

[HighCommander4]

I've been exploring an alternative approach here for the shorter-term: reimplementing CXXRecordDecl::lookupDependentName() in HeuristicResolver so that the implementation can call into other HeuristicResolver helpers.

[HighCommander4]

I've been exploring an alternative approach here for the shorter-term: reimplementing CXXRecordDecl::lookupDependentName() in HeuristicResolver so that the implementation can call into other HeuristicResolver helpers.

Proposed fix following this approach: https://reviews.llvm.org/D153248