rb_yield_block      7 ext/-test-/iter/yield.c     return rb_block_call(self, rb_to_id(argv[0]), argc-1, argv+1, rb_yield_block, 0);
rb_yield_block   1840 include/ruby/ruby.h VALUE rb_yield_block(VALUE, VALUE, int, const VALUE *, VALUE); /* rb_block_call_func */