how to instrument dmd compiler to dump all references to a given symbol?

[Timothee Cour]

eg:

how to instrument dmd compiler to dump all references to a given symbol?
eg: for `A.a` it should output the locations marked with HERE
any help/starting points would be appreciated!

```
Struct A{
int a;
 void fun(){
  a++; // HERE
  alias b=a;
 b++; // HERE
 }
}

void fun(){
 int a; // NOT HERE
 A b;
 b.a ++ ; // HERE
}
```