Difficulty: Medium · Puzzle 2 of 6 · Topic: Virtual Method Puzzles
Why does this class fail before simulation even starts, and what exact fix is required?
class base_cfg;
int id;
function new(int id);
this.id = id;
endfunction
endclass
class ext_cfg extends base_cfg;
function new();
// no super.new call
endfunction
endclassConstructors are not optional in inheritance when base has required parameters.
1) `base_cfg` has no zero-argument constructor; it requires `id`.
2) `ext_cfg::new` must call `super.new(<id>)` as the first statement.
3) Without it, compilation/elaboration fails due to unsatisfied base constructor call.Answer: It is illegal because base constructor needs an argument and `ext_cfg` never calls `super.new(id)`.
Candidates coming from other languages assume base default constructor is auto-synthesized.
How would you thread this constructor argument from UVM factory `create` path in components?