if a method `foo` uses a block, other (unrelated) method `foo` can receives a block. So try to relax the unused block warning condition. ```ruby class C0 def f = yield end class C1 < C0 def f = nil end [C0, C1].f{ block } # do not warn ```
rb_fiber_new
--target-rbconfig
--help
warn
#scan_byte
#peek_byte