vlib/v/checker/tests/interface_generic_err.vv:8:1: warning: unused variable: `why`
    6 | // no segfault without generic
    7 | what := What{}
    8 | why := Why(what)
      | ~~~
vlib/v/checker/tests/interface_generic_err.vv:7:9: error: could not infer generic type `T` in generic struct `What[T]`
    5 | 
    6 | // no segfault without generic
    7 | what := What{}
      |         ~~~~~~
    8 | why := Why(what)
vlib/v/checker/tests/interface_generic_err.vv:8:8: error: could not infer generic type `T` in interface `Why`
    6 | // no segfault without generic
    7 | what := What{}
    8 | why := Why(what)
      |        ~~~~~~~~~
vlib/v/checker/tests/interface_generic_err.vv:8:8: error: `What` does not implement interface `Why`, cannot cast `What` to interface `Why`
    6 | // no segfault without generic
    7 | what := What{}
    8 | why := Why(what)
      |        ~~~~~~~~~
