message: instead of declaring 'double err' as a variable, renamed it to 'err_ip; in gridfunc.cpp since 'err' is already declared as a global variable
diff: @@ -2789,9 +2789,9 @@ double GridFunction::ComputeL2Error(
  {
  const IntegrationPoint &ip = ir->IntPoint(j);
  T->SetIntPoint(&ip);
  - double err = fabs(vals(j) - exsol.Eval(*T, ip));
  - err = pow(err, 2);
  - error += ip.weight * T->Weight() * err;
  + double err_ip = fabs(vals(j) - exsol.Eval(*T, ip));
  + err_ip = pow(err, 2);
  + error += ip.weight * T->Weight() * err_ip;
  }
  }
  // negative quadrature weights may cause the error to be negative
  