[cfe-dev] Interesting problem trying to obtain UsingShadowDecl from DeclRefExpr

[Abramo Bagnara]

namespace ns {
int a;
}

int main() {
  using ns::a;
  return a;
}

I need to relate DeclRefExpr for 'a' to the used UsingShadowDecl, but
DeclRefExpr::getDecl() is designed to give me the target VarDecl instead
of the "bridge".

Is this intentional?

Do I have another way to get this info?

A similar problem is present trying to obtain target UsingShadowDecl
from another UsingShadowDecl.

This is fundamental to build a dependency graph and to detect unused
UsingDecl.