YAKL_SCOPE

In C++, lambdas only capture by value variables defined in local scope. This is a problem in two separate cases: this->var and ::var. In each of these cases, since they are not in local scope, C++ lambdas access them by referencing them from the CPU. This will cause an invalid memory address error inside a device kernel. To alleviate this, please use YAKL_SCOPE( var , this->var ); or YAKL_SCOPE( var , ::var ); to place the variable into local scope so that C++ lambdas copy it by value, making it valid in device memory when used in a device kernel. This statement goes before the parallel_for. For instance:

class Chicken {
  int liver;
  
  void peck() {
    YAKL_SCOPE( liver , this->liver );
    parallel_for( 1 , YAKL_LABMDA (int dummy) {
      liver++;
    });
  }
};

What the YAKL_SCOPE() macro does is create a local reference to the variable, e.g., auto &var = this->var;